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Look after your heart this February

katieguest — Wed, 08 Feb 2012 08:00:50 +0000

February is National Heart Health month which is an initiative supported by the British Heart Foundation (BHF). It is aimed at increasing individuals’ awareness on how to look after the health of their hearts and to ultimately reduce the number of heart disease related deaths. BHF state; “Our vision is of a World where people do not prematurely die of heart disease.”

Eating a diet full of fruit and vegetables is good for supporting a healthy heart (5.)

There are many ways in which we can protect our heart, and bodykind‘s Nutritionists have often written about these. Back in March, Ani Richardson wrote about the benefits of eating a diet full of fruit and vegetables and the benefits of Pecans in relation to heart disease. Nadia Mason wrote about how a daily nutritious smoothie may reduce the risk of diabetes and heart disease in August and in September wrote about Turmeric and Cinnamon being excellent spices for a healthy heart. There is continuous research conducted on heart health and it’s more important than ever to take actions to protect it.

In January this year, the BHF released some statistics (1.) that show heart attack death rates dropped dramatically in the early years of the new millennium, falling by more than half. The research, funded by the British Heart Foundation (which is important to note), showed an average of 5% drop in heart attacks each year from 2002 through to 2010. Whilst these figures are impressive, there are still over 30,000 people who have a cardiac arrest outside of hospital each year – many of who die before medical help arrives. That is why is it so important to prevent a heart attack in the first place – as they say; “prevention is better than cure”.

There are many nutrients that can benefit heart health and an overall balanced and wholefood-based diet full of fruits and vegetables are essential for this. One study (2.) published by the American Journal of Clinical Nutrition in 2011, found that there was a large reduction in coronary heart disease risk in men and women that had a diet rich in green leafy vegetables (such as spinach and kale) as well as olive oil (often associated with the Mediterranean lifestyle).

More specifically, one of the main nutrients which you can include in both your diet and in supplement form for heart health are omega 3 fatty acids. These essential fatty acids are generating a large amount of popularity for their multitude of beneficial health effects. They are found in oily fish such as mackerel, salmon, herring and sardines as well as in flaxseeds, walnuts and soya beans. If you don’t eat fish on a regular basis you may want to consider a fish oil supplement (or flaxseed if you cannot eat fish) in oil or capsule form . One recent study (3.) published in the Annals of Internal Medicine in 2011, investigated circulating Long-Chain Omega-3 Fatty Acids and the incidence of coronary heart disease in 2,735 older adults between 1992 and 2006. The researchers found that the total level of fatty acids circulating in the blood systems of these patients was associated with lower levels of coronary heart disease.

Another study (4.), also in 2011, looked into the possibility that early menarche (a risk factor for developing cardio-metabolic diseases) could be related to vitamin D deficiency in early age. After investigating the plasma vitamin D concentrations for 242 females for an average of 30 months, they found that early menarche was indeed twice as likely in vitamin D deficient females as those that were not vitamin D deficient. The authors concluded that Vitamin D deficiency is associated with earlier menarche and therefore the possibility of increased risk of developing cardio-metabolic diseases. Vitamin D is found in oily fish (again), cod liver oil, eggs and dairy products as well as in supplement forms.

As well as these nutrients, B vitamins (more specifically folic acid, B6 and B12) which are found in whole grains, meat and eggs, help to keep our arteries healthy. Vitamins E and C can also keep our heart healthy and antioxidants and bioflavonoids found in a variety of fruit and vegetables are also a great addition to any diet or supplement regime to reduce the level of free radicals in the body that can harm the heart.

Exercise is also must, even if it’s just a brisk walk around the office car park on your lunch break to get the blood circulating. Aiming for 30 minutes 3-5 times per week is the ideal. Perhaps try walking to the shop instead of driving or take the steps instead of the lift. Why not consider getting a group of friends together and organising a walking or bike-riding club? The possibilities are endless with exercise and it doesn’t have to mean slogging away on the treadmill for hours in the gym!

Written by Katie Guest and Lauren Foster

References

(1.) BHF

(2.) Benedetta, B., Masala, G., Saieva, C. et al (2011) Fruit, vegetables, and olive oil and risk of coronary heart disease in Italian women: the EPICOR Study. American Journal of Clinical Nutrition, Vol. 93, no. 2, 275-283.

(3.) Mozaffarian, D., Lemaitre, R.N., King, I.B., Song, X., Spiegelman, D., Sacks, F.M., Rimm, E.B. & Siscovick, D.S. (2011) Circulating Long-Chain ω-3 Fatty Acids and Incidence of Congestive Heart Failure in Older Adults: The Cardiovascular Health Study. A Cohort Study. Annals of Internal Medicine, 155: 160-170.

(4.) Villamor, E., Marin, C., Mora-Plazas, M. & Baylin, A. (2011) Vitamin D deficiency and age at menarche: a prospective study. American Journal of Clinical Nutrition, Vol. 94, no. 4, 1020-1025.

(5.) Image courtesy of Grant Cochrane

Study links sugary drinks with higher blood pressure

AniKowal — Wed, 27 Apr 2011 05:00:56 +0000

Last year I wrote about a study which found that drinking sugary drinks was associated to increased blood pressure (a risk for heart disease and other health problems). A newly published study (1) has backed up these findings showing that adults who drink sugar-sweetened drinks tend to have higher blood pressure levels.

The study (1) involved UK and US participants of the International Studyof Macro/Micronutrients and Blood Pressure (known as INTERMAP). Over 2500 individuals aged between 40 and 59 were included in the study and various data samples were collected including dietary data, urine and blood pressure readings. Sugary drinks included those containing fructose, glucose and sucrose.

The researchers found that for every extra sugar-sweetened beverage drunk per day (1 serving = 355mL) participants on average had significantly higher systolic blood pressure by 1.6 millimeters of mercury (mm Hg) and diastolic blood pressure higher by 0.8 mm Hg. These figure remained statistically significant even after adjusting for differences in body mass (1).

Systolic blood pressure, represented by the top number in a blood pressure reading, is the measure of the phase of the heartbeat when the heart contracts and pumps blood into the arteries. Diastolic blood pressure, represented by the bottom number in a blood pressure reading, is the measure of the phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.

The study found (1) that higher blood pressure levels were present in individuals who consumed more glucose and fructose, both sweeteners which are found in high-fructose corn syrup, the most common sugar sweetener used by the beverage industry. It was also noted that blood pressure was higher in those individuals consuming high levels of both sugar and sodium (salt).

Sugar intake in the form of glucose, fructose and sucrose was found to be highest in those individuals who consumed more than one sugar-sweetened drink daily. It was also found that individuals consuming more than one serving per day of sugar-sweetened drinks consumed significantly more calories than those who didn’t, with average energy intake of more than 397 calories per day. Those individuals who did not consume sugar-sweetened beverages had lower average body mass index (BMI) than those who consumed more than one of these drinks daily.

In a press release (2) the senior author, Paul Elliott said “This points to another possible intervention to lower blood pressure,” “These findings lend support for recommendations to reduce the intake of sugar-sweetened beverages, as well as added sugars and sodium in an effort to reduce blood pressure and improve cardiovascular health.”

Ian Brown, a research associate at London’s Imperial College UK said (2) “People who drink a lot of sugar-sweetened beverages appear to have less healthy diets,” “They are consuming empty calories without the nutritional benefits of real food. They consume less potassium, magnesium and calcium”. Ian Brown went on to say why sugary drinks may be impacting blood pressure levels: “One possible mechanism for sugar-sweetened beverages and fructose increasing blood pressure levels is a resultant increase in the level of uric acid in the blood that may in turn lower the nitric oxide required to keep the blood vessels dilated. Sugar consumption also has been linked to enhanced sympathetic nervous system activity and sodium retention.”

The study is only an association study, it does not prove that sugary drinks cause higher blood pressure “This is a population study. It’s one piece of the evidence in a jigsaw puzzle that needs to be completed,” said Ian Brown (2) “In the meantime, people who want to drink sugar-sweetened beverages should do so only in moderation.”

As Mr Brown mentions, sugar represents ‘empty calories’, it provides energy without any nutritional benefits. A nutrient rich diet, packed with vitamins, minerals, fibre and flavonoids is one which contains an abundance of vegetables, fruits, beans/pulses, nuts/seeds, wholegrains and other unprocessed, unrefined foods. Cutting back on added sugars is a great step toward better health

(1)Brown IJ et al. Sugar-Sweetened Beverage, Sugar Intake of Individuals, and Their Blood Pressure: International Study of Macro/Micronutrients and Blood Pressure. Hypertension. Published online before print February 28, 2011, doi: 10.1161/HYPERTENSIONAHA.110.165456

(2)Press Release. American Heart Association (2011, March 1). Sugar-sweetened drinks associated with higher blood pressure. ScienceDaily. Retrieved March 2, 2011, from http://www.sciencedaily.com /releases/2011/02/110228163030.htm

Written by Ani Kowal

Bioactive plant compounds in berries may help to reduce high blood pressure

AniKowal — Wed, 09 Mar 2011 05:00:55 +0000

Studies have previously found that flavonoids (bioactive plant compounds), found in various vegetables and fruits, can have beneficial effects on blood pressure when given to individuals in an ‘intervention’ study setting. A new study (1) carried out at the University of East Anglia UK and Harvard University USA and published in the American Journal of Clinical Nutrition has looked at the ‘habitual’ intake of flavonoids by individuals in their normal lives and the impact this may make on blood pressure. They wanted to know if individuals who have high intakes of flavonoids had a reduced risk of hypertension (high blood pressure)

High blood pressure, hypertension, can lead to heart disease and stroke. Around a quarter of the adult population is affected globally, including 10 million people in the UK and one in three US adults (2).

Over 170,000 individuals participated in the study (1). Total flavonoids intakes were calculated from a specialised food frequency questionnaires every 4 years. During 14 years of follow up around 35,000 cases of hypertension were reported. Analysis of the food frequency questionnaires showed that individuals consuming the greatest intakes of anthocyanin, a flavonoids, predominantly from blueberries and strawberries, had an 8% reduced risk of hypertension compared with individuals eating the lowest amounts. The risk reduction was 12% in participants aged 60 years and younger (1). The positive effects on blood pressure were stronger for blueberry rather than strawberry consumption. The study found that compared with those who do not eat blueberries, those eating at least one serving a week reduce their risk of developing the condition by 10% (2).

Anthocyanins are flavonoids found in high amounts in berries such as blackcurrants, raspberries and blueberries as well as aubergines and blood orange juice. In a press release (2) lead author, Professor Cassidy, of the study said “Our findings are exciting and suggest that an achievable dietary intake of anthocyanins may contribute to the prevention of hypertension,” “Anthocyanins are readily incorporated into the diet as they are present in many commonly consumed foods. Blueberries were the richest source in this particular study as they are frequently consumed in the US. Other rich sources of anthocyanins in the UK include blackcurrants, blood oranges, aubergines and raspberries.”

The study was an association study and does not prove that flavonoids reduce the risk of hypertension. However, the researchers are now planning the next stage of their research where they will conduct randomised controlled trials with different dietary sources of anthocyanins to define the optimal dose and sources for hypertension prevention. The researchers hope that this follow up study will enable the development of targeted public health recommendations on how to reduce blood pressure (2).

Flavonoid supplements are available to buy in the UK, however supplements should never be used as an alternative to a healthy diet and it is always advisable to see a medical doctor prior to beginning any supplement regimen. Including a variety of different vegetables, fruits and wholegrains in the diet will help to provide the body with a range of different flavonoids. Eating these whole fruits and vegetables will also provide a range of vitamins, minerals and fibre which may further reduce the risk of developing various health problems.

(1) Cassidy A et al. 2011. Habitual intake of flavonoid subclasses and incident hypertension in adults. Am J Clin Nutr. 93(2):338-47.

(2)Press release. University of East Anglia (2011, January 15). Bioactive compounds in berries can reduce high blood pressure. ScienceDaily. Retrieved January 24, 2011, from http://www.sciencedaily.com /releases/2011/01/110114155241.htm

Written by Ani Kowal

Study finds that watermelon seems to be effective in blood pressure lowering

AniKowal — Mon, 20 Dec 2010 05:00:10 +0000

Last year I wrote about Watermelon and how it contains an amino acid (the building blocks of protein) called citrulline. This amino acid is converted in the body to arginine. In turn arginine is used in the body to produce nitric oxide which causes blood vessels to relax, or dilate, and allow increased blood flow. Studies have found that consumption of watermelon juice boosts blood plasma arginine levels. Increasing blood flow may be important in reducing heart and circulatory conditions via blood pressure reducing effects.

A new study (1) has now found that watermelon may be an effective natural weapon against prehypertension (high blood pressure), a precursor to cardiovascular disease.

92% of watermelon is made up of water but the remaining 8% is full of nutrition. Watermelon is a good source of flavonoids (naturally occurring plant chemicals with health benefits) and the carotenoids, lycopene and beta carotene as well as vitamin B6, vitamin C and potassium. It also contains fibre and, as mentioned above, an amono acid called citrulline.

This recent study (1) evaluated the effects of watermelon supplementation blood pressure in individuals with pre-hypertension. The study actually used supplemental L-citrulline from a watermelon extract. When administered daily for 6 weeks there was an improvement in the function of the arteries and a consequent reduction in blood pressure in all individuals. In a press release one of the study authors said (2)”We are the first to document improved aortic hemodynamics in prehypertensive but otherwise healthy middle-aged men and women receiving therapeutic doses of watermelon,” “These findings suggest that this ‘functional food’ has a vasodilatory effect, and one that may prevent prehypertension from progressing to full-blown hypertension, a major risk factor for heart attacks and strokes”. “Given the encouraging evidence generated by this preliminary study, we hope to continue the research and include a much larger group of participants in the next round,”

Watermelon is the richest natural, edible, source of L-citrulline. In the body citrulline is converted to arginine, which as mentioned above is essential for nitric oxide formation that helps to regulate healthy blood pressure. The study is important since giving arginine supplements isn’t always an option, arginine can cause nausea and gastrointestinal upset in some individuals. Citrulline and watermelon are well tolerated with little or no side effects

In the press release (2) one of the study authors also said “Individuals with increased blood pressure and arterial stiffness — especially those who are older and those with chronic diseases such as type 2 diabetes — would benefit from L-citrulline in either the synthetic or natural (watermelon) form,”"The optimal dose appears to be four to six grams a day.”

Before deciding to use citrulline, or any supplement, for blood pressure regulation it is important to visit your medical doctor.

(1)Figueroa A et al. 2010. Effects of Watermelon Supplementation on Aortic Blood Pressure and Wave Reflection in Individuals With Prehypertension: A Pilot Study. American Journal of Hypertension. E-pub prior to print DOI: 10.1038/ajh.2010.142

(2) Press release. Florida State University (2010, October 13). Watermelon lowers blood pressure, study finds. ScienceDaily. Retrieved October 14, 2010, from http://www.sciencedaily.com /releases/2010/10/101013173847.htm

Written by Ani Kowal

Cutting down on sugary drinks may lower blood pressure

AniKowal — Wed, 08 Sep 2010 05:00:17 +0000

High blood pressure is associated with an increased risk of heart disease and other health problems. Eating a healthy diet rich in fruit and vegetables and oily fish, which are rich in omega 3 fatty acids, and low in salt is associated with a reduced blood pressure. A recently published study (1) has found that drinking fewer sugar-sweetened drinks may lower blood pressure.

The authors of the study note (1) that an increased consumption of sugar-sweetened drinks is associated with an increased risk of obesity, metabolic syndrome (a risk for heart disease and diabetes) and type 2 diabetes. The researchers wanted to study the relationship between sugar-sweetened drinks and blood pressure. The study involved over 800 adults who were participating in an 18 month behavioural intervention trial. Blood pressure and dietary intake were measured at the start of the study and then again at 6 months and 18 months. Specialised models were used to estimate the changes in blood pressure and the relationship between sugar-sweetened drink consumption.

The researchers found (1) that a reduction of one serving per day of sugar-sweetened drink was associated with a 1.8mmHg reduction in systolic blood pressure over 18 months and a 1.1 mm Hg decline in diastolic pressure over 18 months. After additional adjustmentfor weight change over the same period, a reduction in sugar-sweetened drink intakewas still significantly associated with reductions in systolicand diastolic blood pressures. Reduced intake of sugars wasalso significantly associated with reduced blood pressure. No associationwas found for diet beverage consumption or caffeine intake andblood pressure. The researchers conclude that “Reduced consumption of SSB [sugar-sweetened beverages] and sugarswas significantly associated with reduced BP [blood pressure]. Reducing SSB andsugar consumption may be an important dietary strategy to lowerBP”

In a press release the lead study author said “Our findings suggest that reducing sugar-sweetened beverages and sugar consumption may be an important dietary strategy to lower blood pressure and further reduce other blood pressure-related diseases,” “It has been estimated that a 3-millimeters of mercury (mm Hg) reduction in systolic blood pressure should reduce stroke mortality by 8 percent and coronary heart disease mortality by 5 percent. Such reductions in systolic blood pressure would be anticipated by reducing sugar-sweetened beverages consumption by an average of 2 servings per day.”

In this study, sugar-sweetened beverages were defined as drinks sweetened with sugar or high-fructose corn syrup including regular soft drinks, fruit drinks, lemonade and fruit punch. According to the study authors (2) the research results potentially have important public health implications, because even small reductions in blood pressure are projected to have substantial health benefits on a population level. The lead study author also said “Although this study was conducted among mostly overweight adults and many with hypertension, we believe that others will benefit by reducing the consumption of sugar-sweetened beverages,” “However, such evidence from humans is lacking, and we plan to conduct such research among non-hypertensive individuals.” The study only shows an association between sugary drinks and blood pressure and is not conclusive. The researchers say that further controlled trials are needed to establish whether there is a cause and effect relationship between drinking sugar-sweetened drinks and blood pressure changes.

For more information about blood pressure please read this previous post. The British Heart Foundation(1) have a booklet on blood pressure with more detailed information on why blood pressure maintenance is important, the causes of high blood pressure and detailed advice on how to reduce it. The booklet can be downloaded from their website.

(1)Chen L et al. Reducing consumption of sugar-sweetened beverages is associated with reduced blood pressure: a prospective study among United States adults. Circulation. 121(22):2398-406.

(2) Press release. American Heart Association (2010, May 24). Drinking fewer sugar-sweetened beverages may lower blood pressure. ScienceDaily. Retrieved May 25, 2010, from http://www.sciencedaily.com /releases/2010/05/100524161244.htm

Written by Ani Kowal

Study finds fish oil may be useful for overweight teenagers

AniKowal — Wed, 04 Aug 2010 05:00:29 +0000

Oily fish, such as salmon, trout, mackerel and sardines, and fish oil supplements provide the body with the long chain omega 3 fatty acids (EPA and DHA) that are so important for health and which I write about so frequently. In adults there is indication that fish oil is important for heart health, it can help to lower blood pressure and seems to have beneficial effects on cholesterol levels.

A newly published study (1) has found that fish oil supplements might be useful for lowering blood pressure in overweight teenage children. This could be important for heart health in later life.

The study researchers wanted to investigate whether fish oil affects cardiovascular (heart) risk factors during the time of adolescent growth spurt (1). The study was small, involving 78 teenage boys, aged 13-25, who were slightly overweight. The boys were given either fish oil, which provided 1.5g of long chain omega 3 fatty acids daily, or vegetable oil (the control group) for 16 weeks. Neither group knew whether they were taking the fish oil or the vegetable oil since the oils were ‘hidden’ in bread.

After 16 weeks (1) the group eating the fish oil infused bread had higher concentrations of the long chain omega 3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) in their red blood cells than the group eating the vegetable oil bread, indicating that the fish oil was being well absorbed and incorporated into the body. The systolic blood pressure was around 3.8mm Hg lower and diastolic blood pressure was around 2.6 mm Hg lower in the fish oil group compared with the control group. The changes in red blood cell EPA content were inversely correlated with the changes in systolic and diastolic blood pressure i.e. the higher the EPA content in the blood the greater the reduction in blood pressure.

The findings are significant since, in adults a drop in blood pressure of 3 mm Hg corresponds to at least a 15% reduction in the risk of stroke. In addition to this, blood pressure has been shown to track into adulthood: children and teenagers with higher blood pressure seem more likely to suffer from high blood pressure later in life. High blood pressure is a risk factor for stroke and heart disease. More research is certainly needed before any recommendations can be made for fish oil supplementation for heart protection in children however, research showing the benefits of omega 3 fatty acids for health is vast and ever growing. It would seem sensible to introduce young children to the taste of oily fish early in life and to make oily fish a regular (twice weekly) part of the diet, especially since here in the UK many individuals do not include fish as a regular part of their weekly diet. If you want to consider a fish oil supplement for yourself or your children it would be worth checking with a medical doctor prior to starting a new regimen.

(1)Pedersen MH et al. Effects of Fish Oil Supplementation on Markers of the Metabolic Syndrome. The Journal of Pediatrics. E-pub prior to print online May 17, 2010. doi:10.1016/j.jpeds.2010.04.001

Written by Ani Kowal

A few pieces of dark chocolate Easter egg might be good for the heart

admin — Mon, 05 Apr 2010 09:14:18 +0000

Yesterday was Easter Sunday and I expect that there are still plenty of Easter eggs and chocolate lurking in many homes?! If you happen to have received a dark chocolate egg made from cocoa-rich chocolate (at least 70% cocoa solids) this could be good news for your health. A newly published study, in the European Heart Journal, (1) has found that chocolate consumption appears to reduce the risk of cardiovascular disease (heart disease and stroke), possibly through reducing blood pressure.

Previously I have written about good quality dark chocolate in relation to a number of health benefits. It seems as though cocoa can have an impact on many parameters of health and has been linked to a reduced risk of heart disease, cancer, stress, inflammation, sunburn and more.

This study (1) aimed to investigate the association of chocolate consumption with blood pressure and the incidence of cardiovascular disease. The authors of the study examined published data from a large trial which included over 19,000 individuals who were free from heart attack and stroke at the beginning of the trial and who were not taking medication for high blood pressure. After about 8 years there had been over 150 cases of heart attack and over 130 cases of stroke. Analysis of the data found that individuals who had the highest chocolate consumption had significantly lower blood pressure than those consuming the least. The risk of heart attack and stroke, combined, was also lower in the high chocolate consumers. The current study only shows an association between chocolate and reduced risk of cardiovascular disease, it does not prove that chocolate is responsible. The authors of the study call for further research, particularly randomised trials where chocolate is supplemented to individuals.

It is also incredibly important to add that only small amounts of chocolate were being eaten in the so called ‘high’ consumption group (1). It amounted to an average of 7.5g per day, or around 52g per week, which is the equivalent of half a standard, 100g, size bar of dark chocolate per week. Those who were eating the least were having less than 2g per day. The results did show that those who ate the most chocolate had lower blood pressure and a 39% lower risk of having a heart attack or stroke than those who ate the least amount of chocolate.

It is thought that the flavonoids (plant compounds) in cocoa are responsible for some of the health benefits of dark chocolate. Flavonoids have a high antioxidant potential and have been linked to a reduced risk of all sorts of health problems such as heart disease and certain cancers. In addition to antioxidant bioflavonoids cocoa contains a number of minerals such as magnesium. Dark chocolate also contains fibre and is much lower in sugar than milk chocolate, so most people find that they need far less to satisfy their chocolate cravings.

Antioxidants help to prevent cell damage in the body and protect against disease by mopping-up destructive unstable oxygen molecules known as ‘free radicals’. The flavonoids in cocoa also seem to have other protective effects on the heart and blood vessels too. They seem to prevent blood clotting, abnormal heart beat and blood vessel narrowing. As yet scientists are not exactly sure of specifically how these plant compounds act.

The major flavonols to be found in cocoa are called epicatechin and catechin, cocoa also contains procyanidins. The important message is that dark chocolate (minimum 70% cocoa solids) and cocoa rich products can be enjoyed in moderation and as part of a healthy balanced diet. Such a diet will be rich in bioflavonoids from other sources, especially vegetables, fruits, nuts, seeds, pulses, beans. Vegetables and fruit should form the core of a healthy diet and getting a good variety will give the body many of the nutrients that are needed for optimal health. Flavonoid supplements are now available, though the evidence for their use is still in the early stages. If you feel your diet is lacking in vegetables and fruits you may want to consider a supplement to top-up and cover the shortfall, but remember supplements can never be viewed as a replacement for a healthy diet.

(1)Buijsse B et al. 2010. Chocolate consumption in relation to blood pressure and risk of cardiovascular disease in German adults. European Heart Journal. E-Pub prior to print. doi: 10.1093/eurheartj/ehq068 First published online: March 30, 2010
Written by Ani Kowal

High salt intake impacts more than just blood pressure

admin — Wed, 02 Dec 2009 18:48:01 +0000

Many individuals are aware of the link between excess salt intake and high blood pressure. Numerous studies exist to back up this link and further studies have shown that it is possible to achieve significant reductions in blood pressure, in individuals with high and normal blood pressure levels, by reducing salt intake.

A research paper just published in the British Journal of Medicine (1) has now found that higher salt intake is associated with significantly greater incidence of strokes and heart attacks. The association seems stronger with increasing intakes of salt (it is a dose-dependent association). A difference of 5 g a day in a person’s usual salt intake was found to be associated with a 23% difference in the rate of stroke and 17% difference in the rate of total cardiovascular disease (heart disease, stroke and other diseases involving the heart and blood vessels such as atherosclerosis). Worldwide, raised blood pressure accounts for around 62% of strokes and 49% of coronary heart disease events. The authors of the study note that (1) “each year a 5 g reduction in daily salt intake at the population level could avert some one and a quarter million deaths from stroke and almost three million deaths from cardiovascular disease worldwide”. A significant finding, furthermore, because of probable imprecision in measurement of salt intake, the authors say that these effect sizes are likely to be underestimated!

The research paper (1) mentions that most adult populations around the world have average daily salt intakes far higher than 6 g, and for many in eastern Europe and Asia have intakes higher than 12 g. The World Health Organization recommended that salt consumption should ideally not exceed more than 5 g per day.

Most of the salt we eat comes from that added to food in the manufacturing process by industry, caterers and food producers. The authors of the paper (1) discuss the fact that In the UK there is a voluntary scheme for the food industry – where there is encouragement for the reformulation of many food items towards a lower salt content and proposals of improved labelling. These efforts have led to a reduction of 0.9 g a day (or about 10%) in population salt intake in four years (from 9.5 to 8.6 g a day), which is still far from the recommended 6 g a day initial targets that were set in the UK. While the voluntary approach is the preferred choice for many governments it may well be time for a more formal ‘regulatory’ approach in order for recommended targets to be reached and for health to be positively influenced.

Practical tips:
*Minimise the amount of processed/refined foods you eat – ready prepared meals are often very high in salt content and other common household staples, such as bread, can also be packed with added salt.
*Always check the label to view the salt content of foods, salt is often ‘hidden’ in various foods that you wouldn’t expect to contain it e.g. biscuits and condiments to name but a few.
*Instead of adding salt to food at the table or during cooking try using herbs and spices to add flavour
*Visit the Food Standards Agency website for loads more information on salt and health and ways to reduce daily consumption

(1)Strazzullo P et al. 2009. Salt intake, stroke, and cardiovascular disease: meta-analysis of prospective studies. BMJ. 339:b4567,
Written by Ani Kowal

New study finds beetroot juice boosts stamina during exercise

admin — Wed, 12 Aug 2009 16:23:13 +0000

A research team at the University of Exeter has just published results of a study which shows (1) that drinking beetroot juice may help boost stamina and help individuals to exercise for up to 16% longer than they are normally able to, this may be down to the nitrate content of the beetroot juice. The researchers are not yet sure of the exact mechanism that causes the nitrate in the beetroot juice to boost stamina. However, they suspect it could be a result of the nitrate turning into nitric oxide in the body, which can relax blood vessels and increase blood flow.

The research team believes that the findings could be of great interest to endurance athletes. They could also be relevant to elderly people or those with cardiovascular, respiratory or metabolic diseases.

This was a very small, preliminary study which took place in men (1). The participants were given 500ml of organic beetroot juice each day for 6 days before completing a series of tests involving cycling on an exercise bike – the exercise tests ranged from moderate-intensity to severe-intensity. On a separate occasion the same men were given a blackcurrant cordial drink for six consecutive days before completing the same cycling tests. After drinking beetroot juice the group was able to cycle for significantly longer than when they were given the placebo blackcurrant drink. The men also gave blood samples throughout the trial.

The beetroot juice contained around 11.2 mM of nitrate while the placebo blackcurrant juice had a negligible nitrate content. The study was performed ‘double blind’ which means that neither the participants nor the administrators they interacted with knew which of the two agents was being tested, the beetroot juice or the blackcurrant cordial.

On days 4-6 the blood plasma nitrite levels were significantly higher in the beetroot juice phase than in the placebo phase and the blood pressure of participants was also significantly reduced in the beetroot juice phase (other studies have shown that beetroot juice can reduce blood pressure). The authors are not sure how the nitrate in the beetroot juice boosts stamina, but they suspect it is because the nitrate turns into nitric oxide in the body. The research team now hopes to conduct further studies to try to understand in more detail the effects of different nitrate-rich foods on exercise physiology. Nitric oxide in the body helps to relax blood vessels and increase blood flow, hence can be important for reducing blood pressure, in the body.

One of the study authors said in a press release (2): “Our study is the first to show that nitrate-rich food can increase exercise endurance. We were amazed by the effects of beetroot juice on oxygen uptake because these effects cannot be achieved by any other known means, including training. I am sure professional and amateur athletes will be interested in the results of this research. I am also keen to explore the relevance of the findings to those people who suffer from poor fitness and may be able to use dietary supplements to help them go about their daily lives.”

Arginine supplements are available to buy and have been shown to be useful to increase nitric oxide levels in the body. The amino acid, Arginine, is a powerful vasodilator (blood vessel relaxer) and may help to support and maintain healthy blood flow and circulation. Arginine is also an antioxidant and helps support healthy arteries. Beetroot drinks and supplements are also available to by but it is important to remember that supplements should not be viewed as a substitute for a healthy balanced diet and lifestyle. Beetroot is also rich source of vitamins, minerals, antioxidant bioflavonoids (bioactive plant compounds) and fibre and would certainly be a good vegetable to include as part of a varied and balanced diet.

(1)Wilkerson DP et al. 2009. Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. Journal of Applied Physiology (August 6, 2009). DOI:10.1152/japplphysiol.00722.2009
(2) University of Exeter Press release. Beetroot juice boosts stamina, new study shows http://www.exeter.ac.uk/news/featurednews/title,37371,en.php

Written by Ani Kowal

Fill up with flavonoids

admin — Mon, 10 Nov 2008 08:55:45 +0000

As you are aware from my previous posts I champion vegetable and fruit consumption. These treasures are abundant in taste, texture, vitamins, mineral and fibre…..but they are also full of bioflavonoids, or flavanoids (members of the polyphenol family). Flavonoids are bioactive plant compounds which have gained increasing amount of publicity over the last few years. Scientists have been looking into the health benefits of these plant compounds and quite a lot of interesting data has been coming to light.

A yet to be published review article(1) looked at polyphenols (mainly found in grapes) and their role in health and found that these compounds may help to reduce the risk of heart disease. The authors of the study state that “Consumption of grape and grape extracts and/or grape products such as red wine may be beneficial in preventing the development of chronic degenerative diseases such as cardiovascular disease“. Grape seeds, grape skin and grape juice contain many different polyphenols including; resveratrol, anthocyanins and flavonoids – you may be familiar with these names as they are widely available as supplements. In conclusion to this review the authors say “supplementation with grape seed, grape skin or red wine products may be a useful adjunct to consider for a dietary approach in the prevention of cardiovascular diseases, although additional research is required to support such a strategy“

Flavonoids act as antioxidants in the body, helping to prevent cell damage and protection against disease by mopping-up destructive unstable oxygen molecules known as ‘free radicals’ (I have mentioned antioxidants and their role in health previously a number of times). Polypheonols also seem to have other protective effects on the heart and blood vessels. They seem to prevent blood clotting, abnormal heart beat and blood vessel narrowing. As yet scientists are not exactly sure of how these plant compounds act, however they do seem to positively change the way our genes function.

Another recently published study(2) looked at the association between a variety of flavonoids and the risk of cardiovascular disease and stroke. The scientists studied 1950 Finish men aged between 42-60 who were free from prior heart disease or stroke. Participants were followed for an average of 15 years and during this time over 100 strokes and 150 cardiovascular disease deaths occurred. Data analysis revealed that men who consumed the highest amounts of flavonoids had a greatly reduced risk of stroke and there was also a reduced risk of death from cardiovascular disease. The results are unsurprising as fruit and vegetables are the major sources of flavonoids and there is plenty of data to show that these foods protect us from all kinds of diseases including stroke and heart disease. The interesting point comes from the fact that the analysis took into account various vitamin intakes suggesting that the flavonoids themselves make a real impact on health.

Yet another study published just this month (3) highlights the health benefits of flavonoids, this time their potential role in weight maintenance and prevention of weight gain. The researchers of this study looked at the association between flavonoids and BMI (body mass index, a measure of overweight) over a 14 year period in 4280 men and women aged between 55-69 years. The results showed that women with the highest intake of flavonoids experienced a significantly lower increase in BMI over the study period. Again, this is not surprising. Individuals who eat a lot of vegetables and fruits tend not to fluctuate in weight and stay leaner.

Now onto two pieces of research (4,5) which I am particularly fond of as they involve dark chocolate! Readers of my blog will know my penchant for dark chocolate. Dark chocolate containing 85%+ cocoa solids is something I truly adore and really savour the moment of one bitter square slowly melting over my tongue! Drinking black cocoa is also something I enjoy. The health benefits of cocoa have been publicised over the last few years and evidence that cocoa may help in the prevention of many conditions, such as cancer and heart disease, is mounting. Cocoa is packed with great minerals such as magnesium and is also ‘choc’ full of flavonoids.

A very recent study(4) suggests that cocoa consumption may be good for the heart (great news since I would have trouble giving it up!). The researchers investigated the short-term effects of eating either solid dark chocolate or drinking liquid cocoa on blood vessel function and blood pressure. The small study included 45 adults who were overweight but healthy (and not obese) who were, on average, 53 years old. In the first stage of the trial the participants consumed a bar of dark chocolate containing 22g of cocoa powder or a cocoa-free bar. In the second stage the participants drank sugar-free cocoa containing 22g cocoa powder, cocoa containing sugar or a placebo containing no cocoa.

Eating dark chocolate and drinking sugar-free cocoa improved blood vessel function compared to placebo and blood pressure decreased in individuals who ate the dark chocolate bar or drank the sugar-free cocoa, compared to those who consumed the placebo. The researchers conclude by saying “The acute [short term] ingestion of both solid dark chocolate and liquid cocoa improved endothelial [lining of the blood vessels] function and lowered blood pressure in overweight adults. Sugar content may attenuate [reduce] these effects, and sugar-free preparations may augment [improve] them”

The other small study(5) found that flavonoid rich cocoa was associated with a significant increase in blood flow to the brain, as measured via a special sort of ultrasound (Transcranial dopler ultrasound). The authors suggest that their data could indicate a promising role for regular cocoa consumption in the treatment and prevention of stroke and dementia.

These studies were very small and preliminary but I found them interesting!! I would like to add that this is not a plug to justify regular chocolate binges (although it does help me to feel better about my dark chocolate habit)! The cocoa used in these studies, and other studies that link cocoa to health benefits such as lowered risk of heart disease, was high flavanol cocoa and only a very small amount was used daily. Sugary, sweet milk chocolate won’t provide the health benefits discussed (sorry to be the bearer of sad news!).

Flavonoids and polyphenols in general are found abundantly in fruits and vegetables, which are so important for our health. Vegetables and fruit should form the core of a healthy diet and getting a good variety will give the body many of the nutrients that are needed for optimal health. Flavonoid supplements are now available, though the evidence for their use is still in the early stages. If you feel your diet is lacking in vegetables and fruits you may want to consider a supplement to top-up and cover the shortfall, but remember supplements are not a replacement for a healthy diet.

(1)http://www.elsevier.com/wps/find/authored_newsitem.cws_home/companynews05_01042 Mounting evidence shows health benefits of grape polyphenols. Philadelphia October 28. Due to be published in the November issue of Nutrition Research
(2)Mursu J et al. 2008. Flavonoid intake and the risk of ischaemic stroke and CVD mortality in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study. BJN. 100:890-895
(3)Hughes L et al. 2008. Higher dietary flavone, flavonol, and catechin intakes are associated with less of an increase in BMI over time in women: a longitudinal analysis from the Netherlands Cohort Study. Am J Clin Nutr. 88:1341-1352
(4)Faridi Z et al. 2008. Acute dark chocolate and cocoa ingestion and endothelial function:a randomised controlled crossover trial. Am J Clin Nutr. 88:58-63
(5) Sorond FA et al. 2008. Cerebral blood flow response to flavanol-rich cocoa in healthy elderly humans. Neuropsychiatric Disease and Treatment. 4:433-440

Written by Ani Kowal