Cellulose Capsules: Do They Inhibit Green Tea Catechin Absorption?

whey proteinGreen tea is a popular supplement in the diet industry. This popularity relates to evidence that shows that green tea consumption may induce weight loss. The exact reason for the weight loss effects of green tea are not known, but a number of mechanisms may explain the fat loss effects observed. Firstly, green tea is a source of caffeine, and caffeine like all dietary methylxanthines is able to stimulate the sympathetic nervous system, and in the process this may raise metabolic rate and induce fat loss. Alternatively, an amino acid in green tea, l-theanine, may have fat loss effects, although they are not as well described, and possibly not as significant as those of caffeine. Lastly, green tera is a source of polyphenols called catechins (also called flavan-3-ols) and these may also have the ability to increase fat oxidation. Studies on mice suggests that the caffeine, l-theanine and catechins may act synergistically in their fat oxidation effects, although this may not been convincingly demonstrated in humans.

green tea weight loss

Green tea is a good source of a group of polyphenols called catechins. These catechins may have general health effects because of their antioxidant capacity. They may also help to induce fat loss. Catechins may interact with the hydroxypropyl methylcellulose, of which some capsules are made, and this may alter their absorption kinetics. Comparisons of gelatin and hydroxypropyl methylcellulose, the latter appears to alter absorption kinetics of green tea catechins. Drinking green tea, or obtaining the catechins from gelatin capsules may therefore be the better option.

The catechins in green tea have also been shown to have antioxidant effects, and may therefore be useful for improving general health. Drinking green tea provides several hundred milligrams of catechins, and this is the prefered way in which to obtain these polyphenols. Some do not like the bitter taste of green tea and so choose to consume the tea in capsule form. However, some evidence suggests that capsules may inhibit the absorption of catechins from green tea because the catechins and the hydroxypropyl methylcellulose (HPMC), of which some capsules are made, may interact. Additionally, the dissolution rate of capsules and their cellulose fillers may further inhibit the absorption rate, or at least alter the absorption kinetics, of the green tea catechins. This has been suggested to account for the lack of effects of green tea capsules in some studies. Gelatin capsules, tablets or drinking green tea may therefore be the prefered method of consuming green tea in order to maximise catechin absorption.

Eat Well, Stay Healthy, Protect Yourself


Draijer, R. and Duchateau, G. S. 2015. Capsule format may hamper green tea catechin bioavailability. Journal of Nutrition. 145: 2797-2799
Posted in Digestion and Absorption, Green Tea | Leave a comment

The Psychology Of Weight Loss: Too Much Too Soon

whey proteinCurrently there is an epidemic of obesity in Western nations. This epidemic has been slow to appear, and likely results from a gradual transition from a traditional high quality whole food diet to a modern Western affaire. The result is a large number of individuals in Western populations that are either obese, overweight or considerably out of shape. The main problem with the Western diet is that it contains too many refined starches and sugars, and these have detrimental effects on the glycaemic control of the individual, damaging the insulin system and insidiously causing metabolic dysfunction. This dysfunction derails the appetite regulatory system and the energy balance systems of the brain, leading to orexia and limited physical endurance. Weight gain and obesity is not something that occurs overnight, and often it can take decades of consuming a poor quality Western diet until the detrimental effects are prominent. Often it is not until we pass our 20’s that weight gain becomes problematic for health.

weight loss

Exercise is not a requirement of weight loss. In fact, in some instances it can be detrimental. Changing the diet and performing exercise together also increases the risk that the individual will not be able to stick to the dietary changes.

At this stage many take the decision to lose weight. The strategy chosen by most is the use of both exercise and a low energy diet in combination. This is the mainstream accepted method for weight loss, but unfortunately is a poor strategy. Exercising and consuming a low energy diet when a metabolic dysfunction exists in the insulin system is not likely to produce beneficial effects in most individuals. As with all diseases (and obesity and weight gain is a disease, caused by pathological changes), the cause of the disease must be treated and reversed before the symptoms can be overcome. In the case of weight gain, the cause of the disease is the consumption of refined starch and sugars that characterise the Western diet. Trying to lose weight in the face of continued consumption of such foods is akin to King Canute trying to hold back the tide through royal decree. However. Despite the poor success rates of such exercise and dietary restrictions, this is the route that many choose to take.

weight loss

If weight loss is is to be effective, dietary changes should be gradual and permanent. Start with the removal of sugars from the diet, move onto the removal of refined starches, and them from this strong baseline, add further permanent changes that can be followed for life.

To compound the mistake however, many also try to make too many changes too soon. Dietary changes are a good strategy for weight loss, and eating high quality foods should be applauded. However, dietary changes should be gradual and, in particular, they should allow time for adjustment to new foods. Often a completely new diet is adopted in a single day, and this is then accompanied by an overly ambitious exercise programme. Such a strategy runs a high risk of failure because the magnitude of the change is too great, and the new regimen is too far removed from the original lifestyle habits of the individuals. This greatly increases the risk that the individual will not be able to cope with the changes and therefore not complete the programme. Additionally, the idea of dietary change is to provide a new diet that is healthy and that can be followed for life. Drastic changes are often not able to be followed in the long term, and this is especially true if exercise is also included. Gradual and permanent improvements are key.

Eat Well, Stay Healthy, Protect Yourself


Posted in Psychology, Weight Loss | Comments Off on The Psychology Of Weight Loss: Too Much Too Soon

Anthocyanins in Berries Contribute to Antioxidant Effects


Posted in Anthocyanins, Antioxidant, Berries | Comments Off on Anthocyanins in Berries Contribute to Antioxidant Effects

Catehin Content of Various Teas


Posted in Black Tea, Catechin, Darjeeling Tea, Green Tea, Oolong Tea, Tea, White Tea | Comments Off on Catehin Content of Various Teas

Minerals and Heavy Metal Exposure

whey proteinHumans require a number of essential minerals for correct metabolic function. These minerals are divided into categories based on the amount required in the diet. Macrominerals are required in gram amounts, microminerals in milligram amounts and trace minerals in microgram amounts. It is a well known feature of human nutrition that minerals compete for absorption. Divalent cations such as calcium ions, zinc ions, iron ions and copper irons all compete for absorption in the small intestine. This likely relates to the similarity in charge between the minerals and the transport mechanisms that recognise that charge. In addition, minerals can inhibit one another in metabolic pathways and this likely results from a similar charge related interaction with transport proteins and enzymes. Balancing dietary intake is therefore recommended in order that optimal levels of all minerals is obtained in the diet, and further, that these are then absorbed in the correct amounts to satisfy daily needs.

nuts and seeds

Zinc and cadmium may interact in human nutrition. Evidence suggests that those with the highest dietary intake of zinc, also have the lowest urinary concentration of cadmium. The authors predicted mathematically that for every 10 % increase in total zinc intake, there would be a 0.42 % decrease in cadmium concentrations in the urine. Nuts and seeds can be a source of zinc.

Heavy metals can also interact with essential minerals. In many cases, heavy metals such as lead, mercury and cadmium inhibit essential mineral absorption and this creates mineral deficiencies. Higher intakes of essential minerals including both dietary and supplemental form, can however have the opposite effect and actually block the absorption of heavy metals. The interactions are complex and not fully understood but a few have been described. One interaction is that between zinc and cadmium. For example in one study, researcher observed an inverse association between plasma levels of zinc and dietary levels of zinc, with urinary cadmium concentrations. Those with the highest intake of zinc had urinary cadmium concentrations that were 0.04 μg/g lower compared to those with the lowest intake of zinc. Supplemental zinc was inversely associated with blood cadmium and serum cadmium in a dose and duration response manner. Low zinc may therefore increase the risk of cadmium accumulation.

Eat Well, Stay Healthy, Protect Yourself


Vance, T. M. and Chun, O. K. 2015. Zinc intake is associated with lower cadmium burden in US adults. Journal of Nutrition. 145: 2741-2748
Posted in Heavy Metals, Macrominerals, Micronutrients, Trace Minerals, Zinc | Comments Off on Minerals and Heavy Metal Exposure

Latency Period For Nutritional Changes

whey proteinIncreasingly individuals are realising the importance of good nutrition. Good nutrition not only improves physical performance, but also mental capacity and cognitive processes. Part of the reasons for the awakening with regard good nutrition is the large body of readily available information that is present on the internet. This information allows people to research the topic of nutrition and thereby become their own nutritionists. One questions that is often asked from those who make dietary changes regards the length of time it may take for improvements to be seen. This is a difficult question to answer because the number of variables involved is high. However, it is an interesting question and worthy of consideration. A good place to start with such a question is the nutrition of iron deficiency. Those who develop iron deficient states can be given high iron diets and iron supplements. Yet despite these changes, correcting an iron deficiency can take up to two years. This highlights the slow changes that should be expected.

One of the first considerations that can determine the length of latency period to health improvements can be the initial state of health. Generally those who start from a lower baseline with regard their health will see the most rapid changes. Many studies show that the unhealthiest individuals see significant improvements in health with relatively simple changes such as incorporation of tinned beans into their diets. Radically changing the diet of unhealthy individuals can therefore manifest rapid improvements to health and these can be seen within a few weeks. Those with already good health will likely see much smaller changes, and these changes may take a much longer time period to manifest as physically measurable improvements. However, because the changes are smaller, does not mean they are less important. Often the smaller more subtle improvements that allow the obtaining of optimal health can be the most fulfilling and worthwhile. This is especially true for cognitive changes.


Dietary changes can take a considerable length of time to cause physiological changes. In some cases these changes may takes years. In some cases the changes may take a few weeks. This depends largely on the initial state of health of the individual, as well as the initial quality of the diet. Most people will not see considerable improvements in health before 6 months to 1 year of eating high quality foods. Although most changes are continuous, it takes a while for the magnitude of the improvements to be noticed.

Another important variable with regard the rate of improvement from dietary changes is the quality of the baseline diet. Although this relates closely to the state of the health of the individual, the two are in reality distinct variables. Those with already reasonable diets, who likely will have the best health, will see slower improvements that those with poorer quality diets. Again, this does not mean that such improvements are not worth the effort, and often the move from general good health to optimal health can be just as rewarding as the move from ill health to good health. As a rule of thumb, 6 months to 1 year should be allowed for significant improvements in physiological function to manifest after commencing improvements in diet, if the baseline diet is a typical Western diet and the individual is in reasonable health. One last point is that often those consuming a typical Western diet consider themselves healthy because they have no obvious disease, but in reality they are far from optimal health.

Eat Well, Stay Healthy, Protect Yourself


Posted in High Quality Diet, Western Diet | Comments Off on Latency Period For Nutritional Changes

Self Reported Dietary Questionnaires: Are They Effective?

whey proteinBoth nutritionists and researchers use self reported dietary questionnaires in order to obtain information from individuals regarding their nutritional intake. The accuracy of this data is invaluable for interpreting the data supplied by the individual, and therein lies the problem. Studies that have assessed the accuracy of self reported nutrition questionnaires have shown that individuals consistently under report energy intakes, and may also provide inaccurate dietary assessments unless prompted by specific questions. This has lead some researchers to conclude that such methods, when applied to a research setting, are pseudoscience, and that such methods have created an erroneous set of nutritional recommendations akin to fraud. While these may seem strong words, there is no smoke without fire, and in this case some of this opinion is valid. Certainly researchers must be very cautious when analysing self reported questionnaires. However, it may be the case that they take such questionnaires at face value.

dietary survey

Dietary questionnaire have inherent problems associated with their use. This relates to the human tendencies to provide inaccurate information to questions. Underreporting energy intake is a known problem with self-reporting nutritional questionnaires.

One of the advantages a nutritionist may have over a researcher is that they deal with a single individual. This allows the nutritionist to spend time with the individual and this attention can provide clarity regarding any ambiguities in their dietary questionnaire. Asking questions and spending time with the individual is pivotal to advancing the questionnaire to a useable form so that data becomes information. However, in research, this is likely not possible and so the data on the questionnaire must be taken at face value. This therefore translates the errors present in the questionnaire onto the information provided in the study, and this leads to erroneous findings and recommendations. Research into the accuracies of questionnaires have been performed and improvements to methodologies have been made. However, the inherent problems of the human tendency to provide inaccurate responses based on conditioning and misunderstanding remain, and so the basic underlying problems of research questionnaires has not been eliminated.

Eat Well, Stay Healthy, Protect Yourself


Subar, A. F., Freedman, L. S., Tooze, J. A., Kirkpatrick, S. I., Boushey, C., Neuhouser, M. L., Thompson, F. E., Potischman, N., Guenther, P. M., Tarasuk, V., Reedy, J. and Krebs-Smith, S. M. 2015. Addressing current criticism regarding the value of self-report dietary data. Journal of Nutrition. 145: 2639-2645
Posted in Uncategorized | Comments Off on Self Reported Dietary Questionnaires: Are They Effective?

Treating Inflammation with Nutrition

whey proteinInflammation is a necessary physiological reaction by the tissues of animals to damage, infection and invasion by pathogens. This process is highly complex, but is designed to provide defence to tissues by supplying immunological components and physical barriers to possible sites of infection. Acute inflammation is generally considered to be beneficial as it provides immediate short term protection to the animal. However, there exists another type of inflammation that may be detrimental to the health. Chronic inflammation of low grade has been suggested to be responsible for, or associated with, a number of Western lifestyle diseases including cardiovascular disease, cancer, obesity, type 2 diabetes and arthritis. Evidence increasingly points to a poor quality diet as the cause of chronic low grade inflammation, and it should be no surprise that nutritional strategies to improve the diet and reduce chronic inflammation have been shown to be successful in preventing these diseases.


Plant foods are rich in antioxidants. Whole grains contain a group of antioxidants called the alkylresorcinols. Fruits and vegetables are rich in carotenoids, as well as polyphenols such as flavonoids and terpenes. Antioxidants limits the oxidative stress that can result from chronic inflammation.

One of the best strategies for reducing the risk of developing chronic low grade inflammation involves the use of antioxidants. Antioxidants are chemicals found in the diet and can be of of either essential or non-essential status. Many such compounds are derived from plant foods and include essential compounds such as vitamin C and vitamin E as well as non-essential compounds such as carotenoids and polyphenols. Antioxidants are useful in treating inflammation because they reduce oxidative stress through their ability to quench free radical activity. Free radicals are chemicals with unpaired electrons that can damage tissues, and antioxidants are composed in such a way that they can donate electrons to these chemicals, thus inhibiting their potential damaging tissue effects. Because one of the side effects of inflammation is the generation of oxidative stress, antioxidants are useful compounds at treating the symptoms of inflammation and thus negating some of its damaging effects.  

fish oils inflammation

Fish oils contain high amounts of omega-3 fatty acids such as eicosapentaenoic acid and docosahexaenoic acid. These fatty acids can limit inflammation by redressing the dietary imbalance that is inherent in Western foods. Western foods supply too many omega-6 fatty acids (such as linoleic acid and arachidonic acid) and this can be a source of proinflammatory reactions through overproduction of omega-6 derived proinflammatory eicosanoids. A balance of around 3 grams of omega-6 to around 1 gram of omega-3 fatty acids is required to maintain cellular health and prevent inflammation.

Another nutritional strategy that is highly effective at treating chronic low grade inflammation is the use of fish oils. Fish oils are long chain marine oils such as eicosapentaenoic acid (EPA, C20:4 (n-3)) and docosahexaenoic acid (DHA, C22:6 (n-3)) that are found as oils in the flesh of cold water fish. Both EPA and DHA belong to the omega-3 family of fatty acids and they can feed into the omega-3 essential fatty acid pathway. This is useful at treating inflammation because inflammation is regulated by localised hormones called eicosanoids and these hormones are created from omega-3 and omega-6 fatty acids. The balance of omega-3 to omega-6 fatty acids in the diet can strongly influences the direction of inflammation. A ratio of 3 grams of omega-6 to 1 gram of omega-3 fatty acids is required for optimal health, but the Western diet supplies too many omega-6 fatty acids. This creates a proinflammatory state, which can be corrected by supplying the necessary omega-3 fatty acids to redress the dietary 3:1 balance.

ginger turmeric

Compounds found in both ginger and turmeric may inhibit the cyclooxygenase-2 and lipoxygenase enzyme systems that synthesise proinflammatory eicosanoids. In this way regular consumption of either may reduce chronic inflammation. The compounds in ginger (gingerols, shogaols and gingerdiones) and turmeric (curcumin) work in a similar way to non-steroidal anti-inflammatory drugs.

A number of herbs have been shown to possess potent anti-inflammatory effects. Comparisons between herbs and pharmaceuticals shows that herbs can be as effective as pharmaceutical drugs at treating inflammation, but often with much fewer and less severe effects. Ginger is a herb that has consistently been shown to produce potent anti-inflammatory effects. Ginger contains chemicals called gingerdiones, gingerols and shogaols that have a similar activity to non-steroidal anti-inflammatory drugs. In this regard they may inhibit pro-inflammatory eicosanoid synthesis by binding to the cyclooxygenase-2 and lipoxygenase enzymes and thus limit the capacity for tissues to undergo the inflammatory reaction. Turmeric too has been shown to have potent anti-inflammatory effects. Turmeric contains active compounds called curcumin, and these can also inhibit the cyclooxygenase-2 and lipoxygenase enzyme systems, acting in the same way as ginger to inhibit inflammation.

Eat Well, Stay Healthy and Protect Yourself


Posted in Antioxidant, Curcumin, Docosahexaenoic Acid, Eicosapentaenoic Acid, Fish Oils, Ginger, Inflammation, Turmeric | Comments Off on Treating Inflammation with Nutrition

Poverty Associated with Disease: More Evidence

whey proteinThere is a large body of evidence that shows that poverty is associated with disease. This should not be a surprising finding with regard to communicable diseases, because as socioeconomic status increases, housing quality and lifestyle conditions improve significantly and this elevates most away from the squalor that is known to be a causative agent in the spread of disease. By creating sewage systems and clean drinking water for most of the population, the Victorians did much to eradicate communicable diseases from Great Britain for example. It is also not surprising that as socioeconomic status increases, access to higher quality nutrition, particularly protein, increases, and this has beneficial effects on the immune system, lowering the risk of infection. As nation states develop economically therefore, their populations become less susceptible to communicable disease, and this is reflected by are large disparity in such diseases between the rich countries of the West, and the rest of the World.

However, more surprising perhaps is the association between poverty and non-communicable diseases in Western countries. For example, it has been shown that those with the lowest socioeconomic status, living in Western nations, are at higher risk of Western lifestyle diseases such as cardiovascular disease, obesity and type 2 diabetes. This association is difficult to explain because Western lifestyle diseases are associated with the affluence of Western society, making it unclear as to why the poorest in these countries are at highest risk. One explanation is that those with low a socioeconomic status are less able to access high quality foods, and more likely to consume ready made foods containing sugar and refined starches. Recently a study published in the Journal of Nutrition reported that those children living in United States households with an absence of food security had a 4 % higher odds of having asthma. Male children, hispanics, blacks, low birth weight and overweight children had the highest odds of having asthma.


Food insecurity in households of United States residing children increases the odds of having asthma. This fits with other data showing that poor socioeconomic status is associated with Western lifestyle diseases such as obesity, cardiovascular disease and type 2 diabetes. One possible cause for this association may be access to ready made foods containing processed ingredients.

Clearly associations between socioeconomic status and disease exist. However, the cause and effect in these associations are hidden with many confounding variables. Just why the poorest living in the West are at high risk of Western lifestyle diseases, yet the poor living in developing countries are at low risk of these diseases, is not clear. That cheap food in the West often contains high amounts of refined starch, trans fats and sugar is the most likely explanation. While the poor in developing countries can afford only basic ingredients based on whole plant foods, those in the West have access to cheap but processed foods. Education may play a role in this as many individuals living in the West do not understand the requirement for good nutrition, and even those that do may not understand the nuances of creating a healthy eating plan. Whatever the reasons, the association between poverty and Western disease is well established, with asthma being another such disease that may be linked to food insecurity.

Eat Well, Stay Healthy, Protect Yourself


Mangini, L. D., Hayward, M. D., Dong, Y. Q. and Forman, M. R. 2015. Household food insecurity is associated with childhood asthma. Journal of Nutrition. 145: 2756-2764
Posted in Asthma | Comments Off on Poverty Associated with Disease: More Evidence

Contribution of Antioxidants in Blood


Posted in Antioxidant, Urate, Vitamin C, Vitamin E | Comments Off on Contribution of Antioxidants in Blood