It is Valentine’s Day on Sunday and chocolate sales are bound to be high. Readers of this blog may remember reading about my penchant for good dark chocolate (my preferred chocolate is very rich and dark at 85% cocoa solids), well it seems like giving this treat to yourself or a loved-one could really be a stress-buster.
Cocoa and good quality dark chocolate (the 70%+ cocoa solids varieties) have been shown to have numerous health benefits mainly due to their antioxidant capacity in the body. A recent study has found that dark chocolate may also be useful in reducing emotional stress (1).
The study (1) was small and very preliminary but certainly interesting. The study participants were first tested using validated psychological questionnaires to see if they had low or high anxiety traits. They were given 40g of dark chocolate daily for two weeks. Blood and urine samples were collected 3 times during the study – at the start, middle and end. The samples were rigorously tested to see whether various measures of body chemistry of the individuals was changed by the chocolate eating and also to see whether specific processes of gut bacteria was altered.
Interestingly the participants with higher anxiety traits showed a distinct change in their metabolic (bodily chemical processes) profiles when eating the dark chocolate. Dark chocolate was, amongst other things, found to reduce the urine levels of the stress hormone cortisol as well as other body chemicals related to stress. Dark chocolate was also found to partially normalise and correct stress-related differences in specific body chemistry levels as well as the activity of specific gut bacteria (1)
In conclusion the scientists suggest that the study provides strong evidence that a daily consumption of 40 g of dark chocolate daily during a period of 2 weeks is sufficient to modify the metabolism of healthy human subjects (1)
Further studies to confirm these results are needed and the study definitely does not justify chocolate binges! However, reaching for a few squares of good quality dark chocolate may be a soothing way to treat yourself to something indulgent, especially on Valentine’s Day.
(1)Francois-Pierre J. Martin, FPJ et al. 2009. Metabolic Effects of Dark Chocolate Consumption on Energy, Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects. J. Proteome Res. 8 (12), pp 5568–5579
Written by Ani Kowal
On Monday I wrote about phytochemicals in relation to obesity. Bioflavonoids are phytochemicals, or plant nutrient, that I have written about often. Fruit and vegetables and other plant-based foods such as nuts, seeds, pulses, beans are the richest sources of flavonoids. A favoured source of flavonoids for me is cocoa. Cocoa and dark chocolate made from a minimum of 70% cocoa solids are a great source of flavonoids that have 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.
A recent study (1) has found that a high intake of cocoa bioflavonoids may be related to a reduced inflammatory response in the body in patients at high risk of cardiovascular disease (heart disease and stroke). Cardiovascular disease is considered an inflammatory condition. The authors note that “These antiinflammatory effects may contribute to the overall benefits of cocoa consumption against atherosclerosis”.
The study involved forty two individuals at high risk of cardiovascular disease. The individuals received 40g cocoa powder with 500mL skimmed milk or only 500ml skimmed milk for 4 weeks. The regimen was then switched. Before and after each intervention period, inflammatory markers in the cells and in blood serum were evaluated. The results indicate that intake of cocoa polyphenols may positively change inflammatory chemicals in individuals at high risk of cardiovascular disease (1)
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’. 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.
A recent review of published evidence(2) also suggests that there could be a link between cocoa consumption and protection against cancer. The high concentration of bioflavonoids – catechins and procyanidins, found in cocoa and dark chocolate products is thought to be the important factor. As mentioned the anti-inflammatory and antioxidant properties of these bioflavonoids probably also accounts for the cancer protective properties. Studies into cocoa and cancer prevention have been small and are preliminary. Larger trials would be necessary for any definitive evidence.
The major flavonols to be found in cocoa are called epicatechin and catechin. 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 rich in bioflavonoids from other sources, especially vegetables and fruits. 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)Mongas M et al. 2009. Effect of cocoa powder on the modulation of inflammatory biomarkers in patients at high risk of cardiovascular disease. Am J Clin Nutr. 90:1144-1150
(2)Maskarinec G. 2009. Cancer protective properties of cocoa: a review of the epidemiologic evidence. Nutr Cancer. 61(5):573-9.
Written by Ani Kowal