Here is a review of reviews on the health effects of tea, coffee, milk, wine and soft drinks.
If you’ve watched my videos or read my books, you’ve heard me say, time and time again, the best balance of evidence available. What does that mean? When making decisions as important as what to feed ourselves and our families, it matters less what a single study says, but rather what the entirety of peer-reviewed science has to say.
Individual studies can generate headlines like “Study finds There is no link between secondhand smoke and cancer,” but to find out if there is a link between secondhand smoke and lung cancer, it would be best to consult a review or meta-analysis that compiles multiple studies. The problem is that some reviews say one thing; for example, “breathing other people’s tobacco smoke” is a cause of lung cancer” (and other reviews say otherwise), such as the effects of secondhand smoke. are These conversations are insignificant and can also “foster irrational fears.” And while we’re at it, you can please into “actively smoking about 4-5 cigarettes a day” without really worrying about it, so light it up!
Why review articles about the health effects of secondhand smoke? reach such different conclusions? As you can imagine, about 90 percent of reviews written by researchers affiliated with the tobacco industry said it was not harmful, while the opposite number comes from independent reviews, as you can see below and at 1:18 of my video. Friday Favorites: What are the best drinks?. Reviews written conducted by researchers affiliated with the tobacco industry were 88 times more likely to conclude that secondhand smoke was harmless. It was all part of “a deliberate strategy to use scientific consultants to discredit science…” In other words, “the strategic, long-term antidote to the problem of passive smoking… is developing and widely publicizing clear and credible medical evidence that passive smoking [secondhand smoke] “It is not harmful to the health of the non-smoker.”
Can’t we just stick to independent reviews? The problem is that industry-funded researchers have all sorts of sneaky ways to avoid declaring conflicts of interest, so it can be difficult to follow the money. For example, it was found that “77% did not disclose the sources of funding” for their research. But, even without knowing who funded what, most reviews concluded that secondhand smoke was harmful. So, just as a single study may not be as useful as looking at a collection of studies on a topic, a single review may not be as useful as a collection of reviews. In that case, looking at a review of reviews can give us a better idea of where the best balance of available evidence may be found. When it comes to secondhand smoke, it’s probably best not to inhale, as you can see in the graph below and at 2:30 in my video.
Wouldn’t it be great if there were reviews of reviews of different foods and drinks? Voila! Get into “Associations between food and beverage groups and major diet-related chronic diseases: a comprehensive review of pooled meta-analyses and systematic reviews.” Let’s start with the drinks. As you can see below and at minute 2:51 in my videothe findings were classified into three categories: protective, neutral or harmful.
First: tea versus coffee. As you can see in the graph below and at 2:58, most reviews found Both drinks protect whatever condition they were studying, but you can see how this supports my recommendation to drink tea instead of coffee. Every cup of coffee is a missed opportunity to drink an even healthier cup of green tea.
No wonder the soda sinks to the bottom, as you can see below and at 3:20 in my videobut 14 percent of reviews mentioned The protective effects of drinking soft drinks. That?! Well, most of them were references to articles like “High intake of added sugar among Norwegian children and adolescents,” a cross-sectional study that found that eighth-grade girls who drank the most soda were thinner than those who drank the least. Okay, but that was just a snapshot in time. What do you think is more likely? That the fatter girls were fatter because they drank less soda, or that they drank less sugary soda because they were fatter? Therefore, soft drink withdrawal may be a consequence of obesity, rather than a cause, but is considered to have a protective association.
Flaws in the study design may also explain the wine figures, as seen below and at 4:07 in my video. This review of reviews was published in 2014, before the revolution in our understanding of “alcohol” evaporating health benefits,” suggesting that the “alleged health benefits of ‘moderate’ alcohol consumption [may have] finally collapsed”—thanks in part to a systematic error of misclassify former drinkers as if they were lifelong teetotalers, as I revealed in a deep dive into a video series on the topic.
Sometimes there are inexplicable associations. For example, one of the studies on soft drinks found that higher soft drink consumption was associated with a lower risk of certain types of esophageal cancers. Do not tell me. Was the study funded by Coca-Cola? Indeed. Does that help explain the positive studies on milk, as you can see in the graph below and at 5:02 of my video? Were they all simply funded by the National Dairy Council?
As shown below and at minute 5:06, even more conflicts of interest have been detected. found between studies on milk than on soda, and industry-funded studies of all such beverages “are approximately four to eight times more likely to be favorable to the industry’s financial interests.” [study] sponsors than articles without industry-related funding.”
However, funding bias aside, there could be legitimate reasons for the protective effects associated with milk consumption. After all, those who drink more milk may drink less soda, which is even worse, so they may come out ahead. However, it may be about more than just relative benefits. The link between soft drinks and cancer seems a little tenuous and not just because of the studio’s financial connection to The Coca-Cola Company. It is difficult to imagine a biologically plausible mechanism, while even something as universally condemned as tobacco is not universally bad. How I did it explored before, more than 50 studies have consistently found a protective association between nicotine and Parkinson’s disease. Even secondhand smoke can be protective. Of course, you’ll still want to avoid it. Secondhand smoke may lower the risk of Parkinson’s, but increases the risk of stroke, an even deadlier brain disease, not to mention lung cancer and heart disease, which have killed millions of Americans since the Surgeon General’s first report was published, as you can see below and in the minute 6:20 in me video.
Fortunately, by eating certain vegetables, we may be able to get some of the benefits without the risks, and the same can be true for dairy. As I described before, milk consumption is associated with an increased risk of prostate cancer, leading to recommendations suggesting that men may want cut reduce or minimize your intake, but also milk consumption associated with lower risk of colorectal cancer. This appears be an effect of calcium. Fortunately, we may be able to get the best of both worlds if eating Calcium-rich plant foods, such as vegetables and beans.
What does our review of reviews study? conclude What about plant-based foods compared to animal-based foods? We will find out below.
Stay tuned for a comprehensive review of meta-analyses and systematic reviews on major diet-related chronic diseases found in the food groups in What are the best foods?.
The alcohol video I mentioned is Is it better to drink a little alcohol than none?and the Parkinson’s video is Pepper’s and Parkinson’s: the benefits of smoking without the risks. I also mentioned my Dairy and cancer video.
What about diet sodas? See related posts below.
What’s wrong with alcohol? Verify Can alcohol cause cancer? and Do some benefits of alcohol outweigh the risks? for more.
I also have tons of milk. Check here.
My recommendations for the best drinks are water, green tea, and hibiscus herbal tea. Learn more in the related posts below.
