To bring you up to speed: kombucha is a fermented drink product, made by fermenting already-fermented green or black tea. This is why kombucha is called ‘doubly-fermented’ tea. However, if kombucha is fermented for too long or in unsanitary conditions, it can develop very dangerous properties.
One of the molecules found in kombucha is called D-saccharic acid 1,4 lactone (D-saccharolactone). D-saccharolactone has been studied for its ability to prevent colon cancer, diabetes and hyperglycemia.
Unfortunately, more research is needed to determine if D-saccharolactone is an effective protective compound when supplemented or consumed through products like kombucha. D-saccharolactone has been shown to be effective when studied in vitro, meaning outside of the body, in a test tube or petri dish, but more studies are needed to determine if these effects extend to oral consumption of kombucha. It is not uncommon for a compound to be very promising in vitro but not do much when consumed (for example, see glutamine).
What sets kombucha apart from other potentially dangerous food products is how little is known about the strains of toxic bacteria and fungi that make improperly brewed kombucha dangerous.
Dangerous food products can fall into several groups:
Spirulina, an algae sometimes used as a supplement, can be dangerous if it is contaminated with microcystin, a kind of toxin. Spirulina producers are aware of this potential danger, and test spirulina for microcystin.
Some herbal supplements can be toxic if they are contaminated with other species of herbs. Herbal producers run tests to make sure their herbal supplements are pure, and subsequently, safe. For example, Stephania tetrandra is one of the four plants that can make up the traditional Chinese medicine Fang Ji. In the past, it has been contaminated with a toxic plant called Aristolochia fangchi, which can also be called Fang Ji. Anyone that produces Stepania supplements knows to test for Aristolochia.
Other food products, when prepared improperly, become toxic or dangerous. Chicken, for example, can be dangerous if it is eaten raw or undercooked. But while you can use a thermometer to determine how safe chicken is to eat, there is no easy test for determining kombucha’s safety. Unlike spirulina, researchers don’t know what fungi and/or bacteria strains are dangerous in kombucha, and which provide the health effects.
Though kombucha may have potential health benefits, it can be dangerous to drink because many of its risks are still unknown. Unsanitary kombucha can cause death, organ failure, and there’s even been one report of cutaneous anthrax.
Any compound that provides unique benefits, but has also been shown to be toxic, can still be supplemented if the toxicity is carefully controlled for. Unfortunately, the specific toxins in kombucha have yet to be identified. More importantly, more research is needed to determine whether kombucha really does provide unique health benefits. With little proven health benefits, and questionable toxicity, Kombucha cannot be recommended for supplementation or consumption at this time. Future evidence must identify the toxic strains in kombucha, or confirm the unique therapeutic effect of saccharolactone (when consumed through kombucha), for kombucha to be recommended as a health drink.
If you do choose to drink kombucha, it is very important to research the producer. Only purchase kombucha from sanitary producers with properly trained staff. Kombucha is not recommended as a therapeutic or preventative drink. Instead, consider options like black or green tea, or fermented food products like kimchi or sauerkraut.
We’ve been getting a few questions we wanted to quickly clear up:
The way we see it is:
Unless you’re a researcher, we recommend the Stack Guides for most people. They're focused on 16 particular topics instead of overwhelming you off the bat.
Absolutely. The reason this is a collection of PDFs is not only for accessibility (so you can read it on your phone, tablet, or computer), but also because we include lifetime updates. Roughly 2-4 times a year we will go through our Stack Guides and ensure that they reflect the latest evidence. You’ll never have to worry about them being out of date
The introductory price is on until Saturday midnight EST. Once Sunday rolls in, the price will be going up!
Get the Stack Guides now!
By far, the #1 question we get is: "What supplements should I take for _?"
In this case, the blank could be anything, but it's usually about a dozen common things. Fat loss. Muscle Gains. Testosterone. Joint Pain.
Occasionally we get the interesting demographic ones, e.g. seniors or vegetarians.
At the same time, what works for a 50 year old female who is overweight may not be what works for a 25 year old male who is fit. Context matters
And while we solved 90% of supplement confusion over a year ago, we have now finally solved the last 10%
Introducing: The Stack Guides.
The world of supplementation is far more complex than just "good" and "bad." In reality, it's more like "your base" "things that we know work" "things that may work" and "overhyped that are a waste of your money." And that's how we approached our Stack Guides.
The full list of Stack Guides:
Each Stack Guide takes on a common supplement concern. We then break down supplements into four categories - Base Supplements, Proven Options, Unproven Options, and Caution/Overhyped. We cover each supplement and carefully breakdown how to take it.
Once you have all the necessary information, we then talk about Assembling Your Supplement Stack, with different tweaks based on your specific context. After that, we answer some common questions about the supplements featured in the guide. Finally, we cover any cautionary information you should know about.
Put together, the Stack Guides distill our years of work and decades of collective research into an easy-to-follow, step-by-step guide It takes something complicated and makes it so easy that even our moms could use it.
Get our Stack Guides now. It will save you time and money and make supplementation easy-as-pie.
Kombucha is a tea product, known as doubly fermented tea or fungal tea. It’s often claimed to have stronger anti-cancer properties than other teas.
Kombucha comes from the same plant that produces green and black tea, Camellia sinensis. The process of brewing kombucha involves fermenting already-fermented black tea with fungi and bacteria. During fermentation, the tea becomes mildly carbonated, acidic, and acquires its distinct vinegary taste. The fermentation process also produces new bioactive compounds and alcohol. Don’t try getting drunk off of kombucha, since the alcohol content is low and drinking a lot of kombucha can be dangerous.
The most important bioactive compound in kombucha is called D-saccharic acid 1,4-lactone, also known as saccharolactone. Saccharolactone is claimed to exert anti-cancer effects in the colon, and it’s supposed to help with detoxification too.
Unfortunately, the potential potency of saccharolactone, as seen in vitro, is difficult to apply to the human body, for two reasons:
There have not been any human studies done on saccharolactone by itself, or in kombucha.
Improper preparation of kombucha results in toxicity and the risk of death.
While kombucha can be prepared safely, improper sanitation can cause cross-contamination, which leads to the growth of toxic fungi and bacteria. Kombucha is a risky supplement option, since it is difficult to identify toxic strains of fungi. Moreover, further research is needed to identify the bacteria strains responsible for kombucha’s health effects. If kombucha is fermented for longer than a week, it will start to develop these toxic properties.
Kombucha made incorrectly can do a lot of damage to the human body. Case studies examining harm done by kombucha consumption have noted death, organ failure, and even one report of cutaneous anthrax.
Ultimately, there is no proven and significant benefit of drinking kombucha. It’s not a very practical health supplement, considering there’s hardly any evidence for its health effects, but plenty of evidence for the damage it can do. If you do choose to drink kombucha, make sure to purchase it from trustworthy producers with sanitary working conditions and properly trained staff.
NOTE: You can see all sources on our Kombucha page.
Added July 21 2014: An Update on Kombucha: Understanding Risk and Evaluating Toxicity
As Examine.com continues to grow (over 33,000 scientific references now), it's important that we remain versatile and ready for the future. A lot of companies start off successfully but get bogged down as they struggle to scale their operations.
We have no interest in slowing down. There's way too much noise out there already.
As such, we're announcing some changes to help ready ourselves for 2015 and beyond.
Firstly, Dr. Spencer Nadolsky will be stepping down as our director. Dr. Nadolsky found that he missed having one-on-one interactions with people (after all, what's why he became a doctor). With that said, he will remain onboard as our medical editor (his expertise, both in theoretical matters and hands-on, is invaluable). He's not going anywhere!
The good news: stepping up as the new Director of Examine.com is Kamal Patel. With an MBA and an MPH (Master of Public Health) from Johns Hopkins, and on hiatus from his PhD in nutrition at Tufts, Kamal Patel brings the perfect blend of business savvy, big-picture health applications, and understanding the nitty gritty of scientific research (he's been published in peer-review over a dozen times). His larger involvement in our future will only be good news for us (for those that remember us linking to a LifeHacker article on why there's so much confusion over health and nutrition, it was Kamal's broad knowledge that contributed heavily to that article).
Secondly, as we grow, we realize that having a large breadth of expert individuals looking over our research and ensuring we haven't missed any crucial detail only helps everyone. Thus, we are now adding Reviewers to Examine.com. While the Editors will continue to perform the bulk of the primary research, Reviewers will be brought in after our internal discussion has concluded to ensure that nothing is amiss and no theoretical or practical points have been overlooked. The addition of Reviewers lets our team remain versatile and lets us work with knowledge experts without greatly slowing down our research.
As such, we are proud to announce the addition of our first reviewer: Dr. Cassandra Forsythe. Having a PhD in exercise science and nutrition, and also a registered dietitian, she brings a wealth of knowledge to Examine.com. She's already started reviewing our work!
Please be sure to give Kamal and Dr. Cass a very warm welcome on our Facebook page. We're extremely excited to have them onboard.
Today at Examine.com, we bring you a page on Adrafinil, a synthetic stimulant. Adrafinil is a precursor to modafinil, which means adrafinil is metabolized into Modafinil after supplementation. The two compounds have very similar properties.
In fact, a lot of research on adrafinil stopped after it was discovered that modafinil was a more effective option. Adrafinil takes more time to start exerting its effects (since it has to be metabolized first), which meant the faster-acting modafinil is used to treat disorders like narcolepsy. Modafinil also leaves the body faster, which makes it less likely to interfere with regular sleeping patterns.
Both adrafinil and modafinil are being investigated for their roles as nootropic agents, as they have potential for enhancing memory formation. Both supplements are used to reduce sleepiness and improve alertness. Evidence suggests they may even be more effective than caffeine at improving focus.
Though there is no published evidence to suggest adrafinil is bad for the liver, the producers of adrafinil have issued a warning against prolonged usage. Since adrafinil is metabolized in the liver, adrafinil should not be supplemented for more than six months at a time.
Rose Hip has been added to the Examine.com database. Rose hip is a term used to refer to the fruit of rose plants, though it usually refers specifically to the fruits of Rosa canina, or ‘dog rose’.
Rose hip is usually supplemented in a powdered form. Keep in mind, it’s a fruit, so the powder will have calories. Taking rose hip daily can alleviate symptoms of osteoarthritis and rheumatoid arthritis. Taking rose hip consistently over several months will reduce joint inflammation and pain while improving mobility because it reduces the accumulation of immune cells in inflamed tissues.
Rose hip is hypothesized to be able to help with diabetes and obesity as well, but further research and evidence is needed before rose hip can be specifically recommended for anything but arthritis.
Rose hip supplementation uses a high dose, between 5-40g of the dehydrated powder. It’s a fruit, after all. Supplementing rose hip in low doses (like those that can fit in a single capsule) is not effective. Rose hip’s effects are very mild. While supplementation does offer benefits for joint problems, other supplements may be more effective.
We recently wrote a pretty simple article for the Guardian in which we covered a few of the more popular supplements.
There was a bit of backlash, and a lot of accusations were made, including the implication that we shill for supplements. Worst of all, our objectivity was questioned.
Examine.com has never (and will never) recommend any supplement brand. We have five editors from diverse backgrounds who all vet the research we publish (a sixth who is a PhD RD will be announced next week). The entire website is a collaborative effort. And we’ve had a singular focus from day one: evidence-based analysis.
So when Tania Browne posted an article on the Guardian questioning our objectivity, we thought it would be prudent to look at her claims of our purported misrepresentation of the evidence:
The Guardian's article links to the relevant sections on examine.com, where there are over 700 PubMed references citing evidence. - Tania Browne
Yes, our fish oil page has 700+ references. It also has almost 22,000 words. It’s a big page, and thus has a lot of citations. This is not a case of citations to prove the point - it’s a case of proving the point with citations.
Unlike most other citation-based websites, we:
We make it as easy as possible to find our citations for any claim we make, both in the HEM and in our Scientific Research section.
So how do you know whether a scientific paper can be trusted? - Tania Browne
Good point. Which is why we specifically label every study listed in the HEM by its trial design: meta-analysis, double blind, other clinical trials that are not double blind (such as cohort studies), and observational studies with no intended intervention.
Still, there is a reason why the same outcome (“health goal” on our site) for one supplement can have multiple meta-analyses - they are not all created equally. For instance, different meta-analyses can have different inclusion criteria, or different statistical methods. We can cite studies - Should meta-analyses trump observational studies? + Systematic Reviews: Meta-analysis and its problems - that explore how meta-studies are not the end-all be-all of scientific research. It is not enough to read the abstract of a meta-study; you must read the full text.
This is why every single paper cited on Examine.com is subjected to rigorous scrutiny by our scientific team.
It is not hard to read a pubmed abstract and come to a conclusion that is contrary to what the authors found. Prudent research requires one to read the full text and not just the abstract.
We’ll accept blame that our language was not precise enough. You can look at our own glucosamine page to see our more nuanced view. We should have clearly differentiated between knee osteoarthritis (a serious degenerative disease) and other forms of osteoarthritis and less serious joint pain.
For that we accept blame.
With that in mind, let’s look at the actual research findings and the accusations of cherry-picking.
You can see our collation of studies on glucosamine and osteoarthritis here. The single meta-analysis which Tania Browne references is already in our HEM, which we summarized as follows: “A network meta-analysis on glucosamine sulfate found statistically significant pain relief, but deemed that the clinical significance of this pain relief was minimal.”
Except, instead of citing one meta-analysis, we cite six. And our analysis of all of the research (not one meta-analysis but all six of them) finds the following:
There appears to be a small decrease in osteoarthritis symptoms associated with glucosamine (as sulfate, not hydrochloride) which is somewhat unreliable but consistently outperforms placebo on meta-analyses. The magnitude of reduction, however, is somewhat minor but still comparable to acetaminophen (paracetamol). At least three of the meta-analyses also performed funnel plots and found no evidence of publication bias.
And that was our recommendation. Dr. Spencer Nadolsky, dealing with patients who have osteoarthritis, recommends glucosamine instead of acetaminophen. We specifically stated in our recommendation that it is not very potent, that the sulfate version should be used, and that it be used instead of non-steroidal anti-inflammatory drugs (NSAIDs). Glucosamine’s safety profile is well established.
By no means did we mean to imply it was a panacea.
Again - we concur that we should have been more explicit that we were only talking about osteoarthritis, and that instead of saying “it may not be a miracle supplement” we should have stated “it will only provide marginal relief.” We were being pragmatic, but were not clear enough.
In a clinical setting in which a patient is suffering from osteoarthritis, glucosamine is found to be as effective as NSAIDs or paracetamol. This does not mean it is very effective, and it was our mistake in not being clear about that.
We have written extensively about protein on our website.
The recommended daily amount of protein for 19-50 year olds is 55.5g for men and 45g for women. But according to the British Nutrition Foundation, average protein intake is 88g for men and 64g for women. - Tania Browne
Again, this is where one must look deeper into the evidence instead of just looking at the quick conclusion.
The RDA of protein is based on the minimal protein intake required to ensure no bone or muscle loss. This recommendation is based on a bodyweight and lifestyle that is now outdated due to the obesity epidemic.
Tania Browne commented that Dr. Nadolsky likes to lift weights (how is that relevant?), as if his hobby influences his dietary recommendations. Our suggested protein goals are, in fact, much lower than what most bodybuilders consume. We've summarized all of the research on how much protein you need.
In 2010, a Consumer Reports survey of 15 brands in the US found that some protein drinks were contaminated with heavy metals that could reach harmful levels in the recommended three daily servings. - Tania Browne
Another example of looking at only a subset of the data, not all of the data. Consumer Reports did indeed find contaminants in protein powders. But if you look at other everyday foods, similar amounts of contaminants were found. And here is the FDA’s larger dataset.
With that in mind, the 2010 testing found three positives out of 15 samples, which is not robust enough to serve as conclusive evidence that protein powders are harmful. If we extend this logic, then a past meat recall due to bacterial contamination would be enough to “prove” that meat is harmful. Furthermore, we do not recommend any brands.
Lastly, Consumer Reports looked at three servings per day, something we did not recommend. The author’s wording is basic fearmongering, using a subset of data to make protein look far more dangerous than it actually is.
Furthermore, the NHS warns that excessive protein intake can lead to bone demineralisation and osteoporosis. - Tania Browne
It should be noted that this is from a special report and not an official position statement. The 2011 NHS special report does indeed mention that protein could play a role in bone demineralization, although this contradicts the positions of other organizations like Osteoporosis Canada.
In cases where there is a dispute in positions, we can defer to the studies conducted. We find in epidemiology that low to normal protein intake is predictive of bone loss and higher protein intakes above the RDI are protective relative to lower intakes. This has been observed in other studies as well. Elderly women with a high calcium intake consuming up to 72g of protein a day slowly improved their bone mineral density. In this same study, the group that only took between 16-50g of protein experienced the greatest bone loss.
The studies showing bone loss are essentially non-existent. They were logically extended from initial studies showing increased calcium elimination in the urine with protein intake, and while at this time it seemed logical to assume that protein caused bone loss, the theory just didn’t pan out in interventions. For those who want to read more on this topic, here is a free in-depth review from the American Journal of Clinical Nutrition about the interactions of protein, calcium, and bone health.
More fearmongering with no basis in evidence.
And a recent article in the journal Cell linked high intakes of animal protein to cancer and higher overall mortality in the under 65s. - Tania Browne
We actually analyzed this exact study. And just as we have repeatedly stated, one must read deeper than the abstract.
That very study she linked to only looked at people over the age of 50. It split people into two groups, and found that increased “protein” was beneficial for those older than 65. We state protein in quotation marks because all protein sources were treated equally - be it chicken breast or bacon-wrapped sausages. The NHS also agrees that said study did not find protein intake to be bad.
This ties into an important point - when it comes to epidemiologic studies, it is important that one read the full text and not simply rely on the abstract stating the basic conclusion, and instead focus on the nuances underlying the claim and to which specific demographics the claim can apply to. As someone studying epidemiology, I'm sure the author can agree with that
Protein is an essential macronutrient, and we only recommended protein powder for its convenience. Worries about it having negative effects at the dosage we recommended is unnecessary.
We will admit that we lost some of our nuance in our recommendation. Our own page on do I need a multivitamin? states the following:
Multivitamins are very useful if you have a poor diet, but they lose much of their benefit if you have a good diet. Many people with good diets take multivitamins unnecessarily. Just supplement the nutrients you need instead.
And that is our entire ethos. Supplementation is done in a targeted manner, and only after your diet is taken into consideration. Identify your deficiencies, and either fix your diet (preferable) or supplement.
In fact, multivitamins might make things worse - Tania Browne
To be blunt, while multivitamins have pretty much no evidence of being beneficial, to say that they “make things worse” is another case of fearmongering.
If we look at only negative effects, excess vitamin E (400 IU) has been associated with an increase in mortality and excess beta-carotene, in smokers, has been associated with an increase in lung cancer. Concerns about multivitamins in a nonsmoker can be negated by simply reducing the vitamin E content. The authors of the meta-analysis that found an increased mortality risk stated that, since most of the studies were done on metabolically unwell people, they are uncertain if the information applies to healthy individuals. Another meta-analysis specifically examining multivitamins finds no impact on mortality.
Multivitamin benefit or detriment is not a clearly agreed upon topic among researchers. Studies within the large meta-analysis include different populations and have widely different results. To say they make things worse is incorrect.
It has been interesting to see vitamin D go from hype to backlash. The Lancet recently published some studies, and you can see our analysis on their study on vitamin D and osteoporosis prevention. We then summarized vitamin D’s utility in our The Truth about Vitamin D analysis.
Worryingly, Nadolsky also advises 50 micrograms (2,000 IU) of vitamin D per day - Tania Browne
Yes, Dr. Nadolsky did indeed recommend 2,000 IU of vitamin D daily. However, why was this worrying? The lowest dose with any adverse (not toxic) effect that has even been noted was a nonsignificant increase in fat gain at 5,000IU.
2,000IU has never been associated with harm, and at times is associated with significantly more benefit than 800 IU. Higher doses (of 5,000 IU or more) have been associated with varying degrees of harm.
The only evidence the author brought forth was a statement of how our recommendation was apparently “twice the NHS recommended maximum intake of 25 micrograms” and how the recommended intake is 5mcg, which is actually wrong in many countries, as 5mcg is 200 IU (vitamin D3) whereas the RDI tends to fluctuate between 400-800 IU depending on the nation (for example, having been recently increased to 800 IU in Canada). The tolerable upper limit in the US is 4000 IU (100 mcg).
In fact, the Endocrinology Society Guidelines recently bumped up their vitamin D recommendations so that "getting 25(OH)D levels consistently above 30 ng/mL may require at least 1500 to 2000 IU/day of vitamin D. This recommendation was tasked by Dr. Holick, who discovered both 25(OH)D and calcitriol.
In short, “high doses” of vitamin D do cause adverse effects, but 2,000 IU is by no means a high dose. We even have a section on toxicity.
Taking too much vitamin D for a long time can cause calcium build up, damaging the kidneys and even softening bones - Tania BrowneThis is true in theory, but only when excess vitamin D is ingested (which as we previously covered, is well above 2000 IU). In short, vitamin D increases calcium utilization and at high doses this occurs in many tissues, which may not actually be beneficial.
Furthermore, vitamin D is thought to have this adverse property because it is in too high a ratio relative to vitamin K. Vitamin K takes calcium out of tissues and reduces calcium buildup in arteries, a reason why the combination of supplements was recommended.
Excess vitamin D can indeed cause harm, but our recommendation of 2000 is not excessive. Any attempt at linking our recommendation to high-dosage vitamin D risks is an illogical leap.
The real science of dietary supplements shows that very few of us need them and most of us will do just fine by eating a healthy, balanced diet. - Tania Browne
We agree, and we have never claimed otherwise. However, there are situations when the diet is not balanced where supplements can be very helpful.
We also agree that our wording for glucosamine and multivitamins was poor. We should have been more nuanced.
With that said, we take our research very seriously. We are 100% independent and neutral, and we readily admit when we are wrong (have been before, and will be in the future). Yet in the case of our original article for the Guardian, properly looking at the actual evidence clearly validates the assertions we made.
Accusations of chicanery and cherry-picking simply do not hold up when the evidence is looked at in-depth. There is a reason why we have five different editors with advanced degrees in different backgrounds (with a sixth who is a PhD RD being announced next week). If anything, Tania Browne’s article engaged in fearmongering and amateur analysis that was not backed by the full body of evidence.
We focus on the entire body of evidence. Our goal is to objectively summarize the scientific research for supplement and nutrition issues, keeping in mind study quality and methodological issues, and provide consumers with the knowledge needed to make informed decisions.
NOTE: This article was vetted by all of our editors
Whew. It's been a journey.
A few days ago, Examine.com turned 3 years old. In those past 3 years we've:
It's been an amazing journey for us, and we're excited to see where the next few years take us!
The guide used to be $39.
For the next 60 hours (from March 17 noon EST until March 19 midnight), it is $29.
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We want to once again thank everyone for their support over the years, and we look forward to continuing to be the source for independent and unbiased information on supplementation and nutrition! We couldn't do it without your support. *Get the Supplement-Goals Reference Guide Now!
After a long period of research, Vitamin E has been examined and added to the database.
The term ‘vitamin E’ refers to a group of eight molecules, which are divided into two major groups: tocopherols and tocotrienols. Alpha-tocopherol is considered to be the main ‘vitamin-like’ molecule, and is often called Vitamin E, while the other molecules are referred to by their individual names.
Vitamin E has a unique role as a dietary supplement, when it comes to immune support. Alpha-tocopherol (200mg) is able to increase the antibody response to vaccinations. It’s also able to fight age-related immunosuppression in the elderly.
A lot of vitamin E’s benefits come from avoiding a deficiency state. A Vitamin E deficiency is associated with a higher risk of falls and bone fractures in the elderly, but taking more vitamin E than is necessary to correct a deficiency will not provide additional benefits.
Superloading vitamin E (727mg/800 IU or more) is associated with a strong antioxidant effect, which has potential for Alzheimer’s therapy, but this amount of Vitamin E also correlates with an increased risk of prostate cancer and mortality. For this reason, superloading vitamin E is not recommended.
Vitamin E is an important molecule that offers benefits for specific populations, like the elderly. Healthy vitamin E levels are supported through as little as 20-30mg of vitamin E a day. Unlike other vitamins, like vitamin D and vitamin K, a sufficient amount of vitamin E can be attained solely through the diet. Avocados, olives, and almonds are high in vitamin E. Vegetable oils, like palm oil, are a widely distributed source of vitamin E. Sesame seeds in particular are great sources of vitamin E, since they also contain sesamin, which improves vitamin E retention.