Tag Archives: hoax

The Green Tea Facade

Green tea has been consumed, mainly by Asian nations (having originated in China) for hundreds and hundreds of years. Over the course of history numerous and powerful heath effects have been attributed to frequent consumption of green tea.

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In the modern day, green tea and green tea based products are major staples of health food and fitness shops with much emphasis placed on it’s ‘fat melting’ properties.

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Green tea has also been linked to other extraordinary benefits…

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  • A cure for various cancers
  • Decreases risk of cardiovascular disease
  • Improves glycemic control
  • Reduces ‘bad’ cholesterol
  • A general reduction in risk of death
  • Reduces inflammation
  • Powerful weight loss aid

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These are all extraordinary claims which of course require extraordinary evidence. Luckily a fair amount of research has looked more closely at these proposed benefits…

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Is green tea beneficial to health: What does the science say?

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I’ve gone through the major ‘health benefits’ of green tea and addressed them below. Where possible I’ve used meta-studies to support my arguments. These are large scale reviews of all the available data on the topic and can provide stronger evidence than individual studies alone.

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Cancer: There are a few studies which make suggestive links between consumption of green tea and reduced risk of certain types of cancer in specific populations. A small decrease in esophageal cancer rates amongst the Chinese and slightly lower rates of oral cancers in Asian populations. (1, 2). However it is impossible to control for all variables in these sort of population studies and although overall cancer rates were very slightly lower in green tea drinkers, there are also many many other differences in lifestyle habits that could lead to this outcome.  When all current data is taken together, there is no firm, conclusive evidence that green tea consumption prevents or treats cancer  (3,4).

Search for 'green tea and cancer' and this is one of the first image results. Most of this is wrong. Pseudoscience like this is why I started this website in the first place. Red writing was added by me not some lunatic arguing with himself in an info graphic.
Search for ‘green tea and cancer’ and this is one of the first image results. Most of this is wrong. Pseudoscience like this is why I started this website in the first place. Red writing was added by me not some lunatic arguing with himself in an info graphic.

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Cardiovascular disease: A recent meta-study which compiled a large amount of data on this subject concluded that daily intake of green tea was associated with  a roughly 5% chance reduced risk of death from cardiovascular diseases (this includes things like heart attacks and stroke) (5). A well respected Cochrane review also compiled data from numerous randomised trials a few years previously and reported a small reduction in blood pressure associated with  tea consumption (6). In fitting with these findings, a number of other studies have suggested green tea consumption may also be associated with a reduced risk of stroke (7).

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Blood glucose control: Data here is a little bit messy. Green tea lowered fasting blood glucose in one trial but data generated on fasting insulin levels as well as glycated hemoglobin levels (used to determine longer term average blood glucose) was inconsistent (8,9). Both these references are large scale meta-studies so we can be fairly certain that green tea consumption has no real impact on glycemic control.

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Cholesterol: In this area green tea does appear to have some small but clear benefits. Another Cochrane review (can’t get enough) of longer term trials over 3 months in duration, concluded that green tea consumption lowers total blood cholesterol concentrations in the blood including LDL (low density lipoprotein) cholesterol sometimes called ‘bad cholesterol’ (10).

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LDL - Bad HDL - Goof
LDL – Bad
HDL – Good

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General risk of death: Two separate meta-studies concluded that frequent consumption of green tea resulted in a small reduction in the percentage chance of death from any cause (11,12).

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Inflammation: Green tea consumption is not associated with a significantly lower concentration of c-reactive protein in the blood. C-reactive protein is an acute phase protein from the liver that increases in response to macrophage and T cell activation so is used as a marker of inflammation (13).

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Green tea and pills containing concentrated green tea extract (catechins being the most important component) are  a multi-million dollar market. Although there is some suggestive evidence of small health benefits (see above), green tea is most commonly sold as a weight loss aid.

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But does it actually help with weight loss?

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Green tea is not a weight loss aid

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If you can convince people that your product will help them lose weight then you will make a guaranteed profit. The population is getting fatter and more than ever, people are desperate for a quick fix for weight problems.

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As you’ve guessed – there is no magic pill or easy fix for weight loss. It requires a maintained change to your eating and exercise habits.

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Ridiculous
Ridiculous

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Green tea is described on lots of product labelling as a ‘metabolic booster’ or ‘fat burner’. The main molecule that is often reported to be the ‘fat burner’ is a catechin called  epigallocatechin gallate (EGCG) . So what sort of conclusions are drawn from study’s looking at the ‘fat burning’ properties of green tea?

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Important point to bare in mind: Your average cup of green tea contains about 50-60 mg of EGCG

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One study from 2009 looked directly at the effects of green tea on body composition, measuring things like intra-abdominal fat, waist circumference and total body fat in control subjects and subjects receiving a varying amount of EGCG and caffeine. The group receiving the highest daily dose of EGCG and caffeine saw a clear reduction in all three measurements (14).

.Sounds great right?

.Well not really.

.This group was receiving 900 mg of EGCG a day as well as 200 mg of caffeine on top.

That’s the equivalent of about 18 cups of green tea and 5 cups of coffee...

Neither of which can be described as ‘healthy’ in the long term.

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Another study, published in 2008 approached from a different angle and looked at if green tea could enhance exercise-induced weight loss.

These participants were receiving over 600 mg of EGCG a day. The paper describes a ‘trend towards greater fat mass  loss in the catechin group’  which is another way of saying there was no statistically detectable difference between the groups. (15).

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What about claims that green tea ‘boost or increases metabolism’?

Short answer: It doesn’t.

A number of studies have shown that green tea consumption has no effect at all on the basal metabolic rate of healthy participants (16, 17). Importantly, these studies were measuring basal or resting metabolism . People peddling ‘fat burning’ green tea supplements want you to believe that green tea will simply burn away the extra calories all while you sit on the sofa. Impossible!

A more recent Cochrane meta-study, taking data from 18 separate studies and involving close to 2000 participants concluded that green tea does lead to small weight loss in obese people. However this is described as ‘non-significant and unlikely to be clinically important’. Additionally, green tea has no effect on weight loss maintenance (18).

All strong evidence that Green Tea or Green Tea Extract products are close to useless when it comes to weight loss. 

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Take home message

 

So what have we learned about green tea…

Commonly advertised attributes and the truth side by side:

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  • A cure for various cancers : No
  • Decreases risk of cardiovascular disease: Small reduction 
  • Improves glycemic control: Currently inconclusive
  • Reduces ‘bad’ cholesterol: Small but clear reduction 
  • A general reduction in risk of death: Potentially true but could be explained by many other variables
  • Reduces inflammation: No
  • Powerful weight loss aid: No

 

Although there is some evidence that green tea consumption can have health benefits such as a reduced risk of death from cardiovascular disease and a reduction in cholesterol, relying on supplements for this benefit isn’t necessary. Reducing your intake of trans fats and exercising more will provide you with these benefits plus many more.

In terms of the fat burning potential of green tea, it simply doesn’t exist. 

If you enjoy green tea then by all means enjoy a hot brew every now and then. However if you are forcing yourself to drink green tea for the advertised benefits  or paying through the nose for green tea extract pills then it’s not worth your time or money.

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Thanks for reading,

ScienceGuy

 

 

 

 

References

 

I recommend using Google Scholar for quick access to these studies.

1) Zheng JS, Yang J, Fu YQ, Huang T, Huang YJ, Li D (January 2013). “Effects of green tea, black tea, and coffee consumption on the risk of esophageal cancer: a systematic review and meta-analysis of observational studies”. Nutr Cancer (Systematic Review and Meta-Analysis). 65 (1): 1–16.

2) Wang W, Yang Y, Zhang W, Wu W (April 2014). “Association of tea consumption and the risk of oral cancer: a meta-analysis”. Oral Oncol (Meta-Analysis). 50 (4): 276–81.

3)  Boehm K, Borrelli F, Ernst E, et al. (2009). “Green tea (Camellia sinensis) for the prevention of cancer”. Cochrane Database Syst Rev (Systematic review) (3): CD005004

4) Johnson R, Bryant S, Huntley AL (December 2012). “Green tea and green tea catechin extracts: an overview of the clinical evidence”. Maturitas (Review). 73 (4): 280–7.

5) Tang J, Zheng JS, Fang L, Jin Y, Cai W, Li D (July 2015). “Tea consumption and mortality of all cancers, CVD and all causes: a meta-analysis of eighteen prospective cohort studies”. Br J Nutr (Meta-analysis). 114: 1–11.

6) Zhang C, Qin YY, Wei X, Yu FF, Zhou YH, He J (February 2015). “Tea consumption and risk of cardiovascular outcomes and total mortality: a systematic review and meta-analysis of prospective observational studies”. Eur J Epidemiology(Systematic Review and Meta-Analysis). 30 (2): 103–13.

7)  Khalesi S, Sun J, Buys N, Jamshidi A, Nikbakht-Nasrabadi E, Khosravi-Boroujeni H (September 2014). “Green tea catechins and blood pressure: a systematic review and meta-analysis of randomised controlled trials”. Eur J Nutr (Systematic Review and Meta-Analysis). 53 (6): 1299–1311

8) Liu K, Zhou R, Wang B, Chen K, Shi LY, Zhu JD, Mi MT (August 2013). “Effect of green tea on glucose control and insulin sensitivity: a meta-analysis of 17 randomized controlled trials”. Am J Clin Nutr (Meta-Analysis). 98 (2): 340–8.

9) Zheng XX, Xu YL, Li SH, Hui R, Wu YJ, Huang XH (April 2013). “Effects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials”. Am J Clin Nutr (Meta-Analysis). 97 (4): 750–62.

10)  Zheng XX, Xu YL, Li SH, Liu XX, Hui R, Huang XH (August 2011). “Green tea intake lowers fasting serum total and LDL cholesterol in adults: a meta-analysis of 14 randomized controlled trials”. Am J Clin Nutr (Meta-Analysis). 94 (2): 601–10.

11)  Tang J, Zheng JS, Fang L, Jin Y, Cai W, Li D (July 2015). “Tea consumption and mortality of all cancers, CVD and all causes: a meta-analysis of eighteen prospective cohort studies”. Br J Nutr (Meta-analysis). 114: 1–11.

12) Zhang C, Qin YY, Wei X, Yu FF, Zhou YH, He J (February 2015). “Tea consumption and risk of cardiovascular outcomes and total mortality: a systematic review and meta-analysis of prospective observational studies“. Eur J Epidemiology(Systematic Review and Meta-Analysis). 30 (2): 103–13

13)  Serban C, Sahebkar A, Antal D, Ursoniu S, Banach M (September 2015). “Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials”. Nutrition (Systematic review & meta-analysis). 31 (9): 1061–71.

14) Wang et al  (August 2009). ”Effects of catechin enriched green tea on body composition” Obesity 18 (4):773-9

15) Maki et al (December 2008) ”Green tea catechin consumption enhances exercise-induced abdominal fat loss in overweight and obese adults” Journal of Nutrition  139(2):264-70.

16) Lonac et al (August 2010) ”Influence of short-term consumption of caffine-free EGCG supplement on resting metabolism and the thermic effect of feeding”.  Obesity  19(2):298-304.

17) Gregersen et al (May 2009) ”Effect of moderation intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions”Journal of Nutrition 102(8):1187-94.

18)  Jurgens et al (December 2012) ”Green tea for weight loss and weight maintenance in overweight or obese adults”.  Cochrane Library 

The Multivitamin Hoax

I was flicking through good old Facebook, the book of face, the other day when I came across an advert for yet another multivitamin product under the name of VITL. Presumably a play on the word vital…as in, you vitally need this supplement to be healthy. Or do you?

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Multivitamin supplements and other products that fall into that sort of category such as anti-oxidant pills are consumed in huge quantities in the UK and US. Many people swear by them and start their day swallowing down a random amount of varied vitamins. Vitamins are good right? They are important in loads of physiological processes so surely more of them is better?

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Looks enticing but 35.99 a month is a bit steep....
Looks enticing but 35.99 a month is a bit steep….

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In reality the science suggests two things rather clearly if you are an average person:

  • All your vitamin needs are met by your diet if its fairly balanced
  • Taking too much of a particular vitamin can have serious repercussions to your health

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I don’t wish to target VITL directly as many companies are peddling their vitamin wares. It’s not the product itself I have an issue with but the target market. It makes medical sense to supplement a vitamin that you are clinically deficient in but trying to sell expensive vitamins to people who don’t need them is a complete waste of the customers money and in some cases potentially harmful to their health.

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What is a ‘vitamin’ 

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 A vitamin can be defined as such :

‘A vitamin is an organic compound and a vital nutrient that an organism requires in limited amounts’ (the key phrase here is ‘in limited amounts’)

Technically speaking, ‘vitamin’ refers to a chemical compound that an organism requires but cannot synthesise by itself in sufficient quantities. The vitamin must therefore largely be obtained from dietary sources.

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Vitamins are classed based on their biological and chemical activity, not on their structure. Therefore a number of vitamin-like compounds (vitamers) may be grouped together under one umbrella vitamin name. For example ‘Vitamin B’ includes a large number of ‘vitamers’ each with their own B number and additional name. Vitamin B9 for example is Folic Acid. Not all vitamers are in the biologically active state but can be converted into this form in the body.

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Thirteen vitamins are currently recognised: Vitamins A, B (8 vitamers), C, D, E and K

 


Physiological Roles

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Vitamins play a varied and diverse role in the body and have widely different functions.

I’ve made a table to summarise this section in brief as it’s fairly in depth!

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vitamin-table-1

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The large group of vitamin B type-compounds  act as co-enzymes (and precursors) in metabolic processes. Co-enzymes are non protein compounds that are required by the protein enzyme to catalyse specific reactions in a cell (1). They therefore perform an extremely important role in the minute by minute function of cells. Acting as co-enzymes is their most recognised functional role but there are many others (2). Large amounts of research effort has been put into uncovering the therapeutic potential of the B vitamin family of compounds. Many do have true therapeutic value but only in the treatment of serve disorders. B9 for example, also known as folic acid, has been shown to reduce the rate of neural tube defects (NTDs) in infants and as a result can be found fortified into many different foods in a hope to reduce the incidence of NTDs in the population (3). There is also some evidence that folic acid supplementation may confer a small reduction in the risk of stroke and cardiovascular disease if taken over a long period of time (4)

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Vitamin D possesses hormone-like functions and act as regulators of mineral metabolism and plays a part in the control of tissue growth and differentiation (5). A chronic lack of vitamin D famously leads to ‘rickets’, a disorder of bone growth and structure. Sunlight (certain wavelengths) modify Vitamin D into its active form which is why at least some exposure to the sun is important. Foods are often fortified with vitamin D in countries that receive lower levels of sunlight (less hours and or/less intensity) but can be found naturally in oily fish and eggs (6).

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Vitamin C acts as both an enzymatic co-factor and also  functions as  an anti-oxidants to protect agasint oxidative stress. The vitamin is a co-factor in a number of important enzymatic reactions, a few of which are related to the synthesis of collagen,  a key structural protein. A lack of vitamin C can impact collagen production leading to scurvy. 

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Yaaaaargh. Eat an orange.
Yaaaaargh. Eat an orange.

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Vitamin C is a well studied vitamin and makes common appearances in health food shops and websites as a sort of ‘cure-all’ especially targeting things like the common cold and other respiratory pathologies (that website link claims you can cure pretty much any disease). However vitamin C supplementation studies have shown conflicting results. A number of studies suggest that vitamin C supplementation may reduce the duration of common colds (7) but it doesn’t seem to prevent colds in the first place (8). The potential protective effects of vitamin C supplements regarding cardiovascular health and lung cancer has also been explored in depth but overall studies suggest no detectable protective effect (9,10,11). Two of these references are systematic reviews and analyse the data from multiple studies. One of which is a Cochrane review who are known to be very thorough in their approach.

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Vitamin E has a number of roles including acting as a fat-soluble anti-oxidant. The vitamin essentially mops up free radicals preventing oxidation stress and tissue damage. This vitamin has also been the subject of a study looking at protective effects against major cardiovascular events in middle aged men but supplementation does not increase protection (12) Surprisingly one report suggested vitamin E supplementation might even increase the risk of lung cancer for already at-risk individuals.(13)

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Vitamin K is required for the complete synthesis of a number of important proteins involved in blood coagulation (various coagulation factors) , vascular biology and bone metabolism (14). In somewhat of a developing theme, vitamin K supplementation was explored as a means to prevent or reduce the incidence of cardiovascular disease. This makes sense as vitamin K deficiency is associated with the stiffening of arteries (15). Despite this, there is no good evidence that vitamin K supplementation will stop cardiac events occurring in the first place (16). The science also refutes fairy common claims that vitamin K supplements can slow cancerous tumour growth (17).

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Overall, studies which look at standard supplementation (rather than the effects of over-supplementation) have produced few promising results. Unless you are deficient in a particular vitamin then supplementation has no detectable benefit to your health. The only possible exception to this is vitamin C supplementation in regards to common cold duration. Additionally, vitamin C supplementation may help in the prevention of common colds when individuals are exercising rigorously in cold environments (18, 19). This seems like a super specific scenario but if you plan on skiing naked for a prolonged period of time than maybe pop a vitamin C tab or two (but not three…that’s just getting silly)

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*Tactical dong strap*

 


Daily multivitamins are potentially harmful

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I’m going to take aim at Berocca here as an example. Berocca is an effervescing tablet that you plop into a glass of water and it releases all it’s tasty, healthy vitamins and minerals (we know the truth berocca you scum bag!). Now, unlike VITL, who I assume have done their research on vitamin absorption, the people behind Berocca have added a ludicrously large % of your RDA (Recommended Daily Allowance) for many of the vitamins. I mean, 1071% of your recommended daily allowance of B1! That is mental for a number of reasons.

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A quick excerpt from the brilliant website quackwatch.org about RDAs:

”The RDAs have been published by the National Research Council approximately every five years since 1943. They are defined as “the levels of intake of essential nutrients that, on the basis of scientific knowledge, are judged by the Food and Nutrition Board to be adequate to meet the known nutrient needs of practically all healthy persons.” Neither the RDAs nor the Daily Values listed on food labels are “minimums” or “requirements.” They are deliberately set higher than most people need. The reason quacks say that the RDAs are too low is obvious: if you believe you need more than can be obtained from food, you are more likely to buy supplements”

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The doses in VITL stay within recommended limits
The doses in VITL stay within recommended limits

 

1000 % of your RDA is 900 % too much!

Firstly I have already shown you that for the average healthy person, supplementing with any vitamin doesn’t provide protection against diseases or make you ‘healthier’ in general. 

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Secondly, vitamins are only required in limited quantity. The phrase ‘more is better’ is almost always wrong when applied to biology. Any additional vitamins taken in are excreted as waste so those doses are needlessly high.

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Finally, those super high percentages may hide a sinister detail. Not only are excess vitamins pointless they have also been linked to increased risk of a variety of diseases. Over-dosing on some of the vitamins can also induce a specific set of symptoms depending on the vitamin as summarised below.

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picture

Major studies looking into the effects of long term vitamin supplementation have produced surprising but solid data.

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General Mutlivitamin Tablets: Two large meta-studies, headed by the same researchers, that had access to data from hundreds of thousands of people (more likely to show a true effect) found that individuals taking daily multivitamins had an INCREASED RISK OF MORTALITY in comparison to people who don’t (20,21). Mortality of course covers death from all causes so those people taking multivitamins daily have an increased risk of dying in general. That’s pretty bleak. Other studies have looked at certain vitamins in particular and their effects on the incidence rates of specific diseases. The situation is no less bleak unfortunately…

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Vitamin A: As the table further up the article shows, vitamin A can be found in green leafy veg, oranges and milk to name just a few sources. Carrots are also a great source. You only need to eat half a carrot to obtain you recommended daily allowance. Now these studies are specific to smokers but beta-carotene (form of vitamin A) was explored for it’s therapeutic value in lung cancer development. Shockingly those smokers on beta carotene supplements saw a 28% increased incidence of lung cancer (which is already comparatively high in smokers), a huge increase! So unexpected was this result that the trial was terminated ahead of schedule. (22, 23)

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The horror!
The horror!

 

Vitamin E: A large number of studies have been conducted concerning Vitamin E supplementation and, like vitamin A, the results are rather disturbing. A study trying to determine if vitamin E could be used to reduce cancer and cardiovascular disease uncovered an increased risk of heart failure in patients taking ‘excessive amounts’ of vitamin E (this why those crazy high % RDAs in some products are dangerous!). These patients all had existing vascular disease or diabetes mellitus (24). Perhaps excessive vitamin E exacerbates circulatory problems that surface with both vascular disease and chronic diabetes.

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Another study produced a similar finding to the Vitamin A meta-studies in that vitamin E supplementation correlated with increased mortality (25). This was a large study involving over 100,000 individuals. The conclusion says it all:

”High-dosage (> or =400 IU/d) vitamin E supplements may increase all-cause mortality and should be avoided.”

Of relevance to men, a more recent 2011 study with 35,000 participants  showed that vitamin E supplementation significantly increased the risk of prostate cancer (26)

Ultimately, the science refutes the phrase ‘you can’t have too much of a good thing’. Multivitamins and specific vitamin supplements have been linked with an increased risk of death in general, prostate cancer in men, skin cancer in women and  heart failure in those already at risk.

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Admittedly, these trials expose participants to vitamin levels far above their recommended allowance but that shows us how potentially dangerous it is for companies to make products (for daily consumption) with 5 or 10 times the recommended levels. 

 


Summary: Do you need daily multivitamin supplements?

 

For the average person, the simple answer is a resounding no. All your vitamin needs are met by your diet.

In fact, it should be an aggressive  ‘no’ because you may in fact actually be damaging your health. If you do still wish to take daily vitamins then for the love of god at least check the % RDA on the back and stay away from those products that provide 1000% of your RDA in one daily serving.

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”2000 percent of my RDA? F*ck that sh*t!”

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Whats important to remember is that although the evidence shows that vitamin supplements, in general, will not make you ‘healthier’ this is all assuming you have a fairly balanced life style and diet to begin with. If you are known to have a deficiency in a particular vitamin then supplementing may still be helpful as long as you stay within recommended daily intakes. Of course, listen to your doctor.

Finally, as an added note: I’ve written this article without touching on fitness or training at all. Not many studies focus on this topic and it would be a very short article if I did. The story is much the same as has been told above. Unless you have a legitimate reason to take vitamins, taking extra won’t effect your general health or really impact your training in any meaningful way. Vitamins are peddled all over fitness and body-building websites just like at health food equivalents but now you know that they are a TOTAL WASTE OF MONEY. 

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My only advice, and this applies to all supplements, is that actual food should always come first. That’s the whole idea of a supplement, to supplement what you are are (or are not) getting through your diet. Your money would be much better spent on frequent purchases of fruit and vegetables.

Any questions? Feel free to reach me at ed@scienceguysupplements.com

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Thanks for reading,

ScienceGuy

 


Text References 

I recommend using Google Scholar to quickly find these studies in full detail.

1) University of Bristol (2002). “Pantothenic Acid”. Retrieved 16 September 2012.

2) National Academy of Sciences. Institute of Medicine. Food and Nutrition Board, ed. (1998). “Chapter 6 – Niacin”. Dietary Reference Intakes for Tjiamine, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin and Choline. Washington, D.C.: National Academy Press.

3) Bailey, Lynn B. (2009). Folate in Health and Disease, Second Edition. CRC Press. p. 198

4) Li Y, Huang T, Zheng Y, Muka T, Troup J, Hu FB (2016). “Folic Acid Supplementation and the Risk of Cardiovascular Diseases: A Meta-Analysis of Randomized Controlled Trials”. J Am Heart Assoc. 5 (8)

5) Holick MF (March 2006). “High prevalence of vitamin D inadequacy and implications for health”. Mayo Clin. Proc. 81 (3): 353–73.

6) Holick, M.F. The Vitamin D Deficiency Pandemic: a Forgotten Hormone Important for Health. Health Reviews. 2010; 32: 267-283.

7) Douglas RM, Hemilä H, Chalker E, Treacy B (2007). Hemilä H, ed. “Vitamin C for preventing and treating the common cold”. Cochrane Database Syst Rev (3): CD00098

8) Heimer KA, Hart AM, Martin LG, Rubio-Wallace S (May 2009). “Examining the evidence for the use of vitamin C in the prophylaxis and treatment of the common cold”. J Am Acad Nurse Pract. 21 (5): 295–300

9) Fulan H, Changxing J, Baina WY, Wencui Z, Chunqing L, Fan W, Dandan L, Dianjun S, Tong W, Da P, Yashuang Z (October 2011). “Retinol, vitamins A, C, and E and breast cancer risk: a meta-analysis and meta-regression”. Cancer Causes Control. 22(10): 1383–96.

10) Ye Y, Li J, Yuan Z (2013). “Effect of antioxidant vitamin supplementation on cardiovascular outcomes: a meta-analysis of randomized controlled trials”. PLoS ONE. 8 (2): e56803.

11) Stratton J, Godwin M (June 2011). “The effect of supplemental vitamins and minerals on the development of prostate cancer: a systematic review and meta-analysis”. Fam Pract. 28 (3): 243–52.

12) Rimm E, Stamper M, et al.(May 1993). ”Vitamin E consumption and the risk of coronary heart disease in men” The New England Journal of Medicine . 328 (20) 1450-1456.

13) Heionen OP, Albanes D (April 1994). ”The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers” The New England Journal of Medicine. 330:1029-1035

14) “Vitamin K Overview”. University of Maryland Medical Center.

15) Maresz K (2015). “Proper Calcium Use: Vitamin K2 as a Promoter of Bone and Cardiovascular Health”. Integrative Medicine (Encinitas, Calif.) (Review). 14 (1): 34–9.

16) Hartley L, Clar C, Ghannam O, Flowers N, Stranges S, Rees K (2015). “Vitamin K for the primary prevention of cardiovascular disease”. Cochrane Database Syst Rev (Systematic review). (9)

17) Ades TB, ed. (2009). “Vitamin K”. American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies (2nd ed.). American Cancer Society. pp. 558–563.

18) Douglas RM, Hemilä H (June 2005). “Vitamin C for Preventing and Treating the Common Cold”. PLoS Medicine. 2(6):

19) Hemilä H, Chalker E (January 2013). “Vitamin C for preventing and treating the common cold”. Cochrane Database of Systematic Reviews. 1

20) Bjelakovic G, Nikolova D, Simonetti RG, et al. Antioxidant supplements for prevention of gastrointestinal cancers: a systematic review and meta-analysis. Lancet. 2004 Oct 2-8;364(9441):1219-28.

21) Bjelakovic G, Nikolova D, Gluud LL, et al. Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: systematic review and meta-analysis. JAMA. 2007 Feb 28;297(8):842-57.

22) Omenn GS, Goodman GE, Thornquist MD, et al. Risk factors for lung cancer and for intervention effects in CARET, the Beta-Carotene and Retinol Efficacy Trial. Journal of the National Cancer Institute. 1996 Nov 6;88(21):1550-9.

23) The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. The New England Journal of Medicine. 1994 Apr 14;330(15):1029-35

24) Lonn E, Bosch J, Yusuf S, et al. Effects of long-term vitamin E supplementation on cardiovascular events and cancer: a randomized controlled trial. JAMA. 2005 Mar 16;293(11):1338-47.

25) Miller ER, Pastor-Barriuso R, Dalal D, et al. Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine. 2005 Jan 4;142(1):37-46.

25) Klein EA, Thompson IM Jr, Tangen CM, et al. Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA. 2011 Oct 12;306(14):1549-56.

Table References

1) Penniston KL, Tanumihardjo SA (2006). “The acute and chronic toxic effects of vitamin A”. The American Journal of Clinical Nutrition. 83 (2): 191–201.

2) “Thiamin, vitamin B1: MedlinePlus Supplements”. U.S. Department of Health and Human Services, National Institutes of Health.

3) Hardman, J.G.; et al., eds. (2001). Goodman and Gilman’s Pharmacological Basis of Therapeutics (10th ed.). p. 992.

4) Brunton, Laurence L.; Lazo, John S.; Parker, Keith, eds. (2005). Goodman & Gilman’s The Pharmacological Basis of Therapeutics(11th ed.). New York: McGraw-Hill.

5) Pantothenic acid, dexpanthenol: MedlinePlus Supplements”. MedlinePlus. Retrieved 5 October 2009.

6) Perry, T. A.; Weerasuriya, A.; Mouton, P. R.; Holloway, H. W.; Greig, N. H. (2004). “Pyridoxine-induced toxicity in rats: a stereological quantification of the sensory neuropathy”. Exp. Neurol. 190 (1): 133–144.

7) FAO; WHO (2002), “ch. 4, Folate and Folic Acid”, Human Vitamin and Mineral Requirements

8) The Dark Side Of Linus Pauling’s Legacy, Quackwatch

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