Coffee health effects – what does the best science say

coffee health effects

Coffee is one of the most consumed beverages worldwide, with tea being number one. And as I have mentioned previously, I am an unrepentant coffee lover. Over the years, there have been a number of claims about coffee health effects, both positive and negative, many without any solid scientific evidence in support.

Claims about coffee health effects goes back centuries. These claims were often confusing and contradictory. How many “studies” have we read about that said drinking it was good for your heart. Or bad for your heart. Or it prevented cancer. Or it increased your risk of cancer.

Part of the confusion is that the popular press, with its strange dependence on false equivalence, often presents two contradictory scientific studies as equivalent, even if they aren’t. Well, we’re going to look at a powerful new study that examined health outcomes that can be related to coffee. Let’s see what they say. Continue reading “Coffee health effects – what does the best science say”

Coffee health benefits – what does the science say?

coffee health benefits

I am an degenerate coffee addict. This has been so since I took my initial drink during my first chemistry finals as a college freshman. My coffee consumption hasn’t decreased much since then. I drink coffee because of its taste and the caffeine. Potential coffee health benefits are, personally, way down the list of reasons for drinking it. And frankly, I’m always skeptical of claimed health benefits for any food, unless there’s some really strong scientific evidence, which is generally lacking.

But recently, news outlets have been touting a couple of robust studies that seem to indicate that there are significant coffee health benefits. For those who know me, I rarely accept popular news sites analysis of scientific research. I think my loyal readers expect me to look at the science and see if there is any validity to the claims made by the press.

Claims about coffee health benefits and claims goes back centuries. It cured alcoholism. Coffee made you work longer. It was good for your heart. Drinking it was bad for your heart. It increases risks of some cancers. Wait, it decreases risks of some cancers. In other words, we really didn’t have vigorous evidence supporting anything definitive with respect to the drink’s health benefits or detriments.

It’s time to look at these two new studies and see what they tell us about drinking coffee. Continue reading “Coffee health benefits – what does the science say?”

Coffee health benefits – is it supported by real science?

coffee health benefits

I am an degenerate coffee addict. This has been so since I took my initial drink during my first chemistry finals as a college freshman. My coffee consumption hasn’t decreased much since then. I drink coffee because of its taste and the caffeine. Potential coffee health benefits are, personally, way down the list of reasons for drinking it. And frankly, I’m always skeptical of claimed health benefits for any food, unless there’s some really strong scientific evidence, which is generally lacking.

But recently, news outlets have been touting a couple of robust studies that seem to indicate that there are significant coffee health benefits. For those who know me, I rarely accept popular news sites analysis of scientific research. I think my loyal readers expect me to look at the science and see if there is any validity to the claims made by the press.

Claims about coffee health benefits and claims goes back centuries. It cured alcoholism. Coffee made you work longer. It was good for your heart. Drinking it was bad for your heart. It increases risks of some cancers. Wait, it decreases risks of some cancers. In other words, we really didn’t have vigorous evidence supporting anything definitive with respect to the drink’s health benefits or detriments.

It’s time to look at these two new studies and see what they tell us about drinking coffee.

Coffee health benefits – the first study

The first study we’re going to examine, from Gunter et al., published in the Annals of Internal Medicine. At a meta level, this epidemiological study was run by respected scientists, with the results published in a very high impact factor (17.2020) journal. Moreover, the study included around 520,000 participants in 10 European countries, which makes it one of the largest studies to date on coffee health benefits.

Compared to some of the horrifically bad studies that we have seen making outrageous claims about this or that food, drink or diet, this study is impressive. This is the kind of study that is equivalent to some of the best vaccine epidemiological research out there.

But what does the results say? To be blunt, they found that drinking more coffee would significant lower a person’s risk to all mortality.

The hazard ratio (HR), which compares the risk of dying between the coffee-drinking and non-coffee groups, was 0.88. In other words, there was a 12% reduction in all death causes in men who were in the upper quartile of coffee consumption. The HR for women in the upper quartile of consumption was 0.93, or a 7% reduction.

Frankly, a 12% or 7% difference in mortality is interesting and intriguing, but from a perspective of evidence-based medicine, it’s difficult to say this is clinically meaningful. However, if there are no known risks to coffee, which would have been uncovered by this study, the importance of those decreases in mortality become more substantial.

There were more significant results for certain diseases. The HR for coffee consumption and digestive disease mortality for men was 0.41 (a 59% reduction), and for women was 0.60 (a 40% reduction). Interestingly, for women, the HR for coffee drinking and circulatory disease mortality was 0.78 and cerebrovascular disease mortally was 0.70. However, the HR for coffee drinking and ovarian cancer mortality was 1.31, or a 31% increase.

The authors concluded, without much wiggle room:

Coffee drinking was associated with reduced risk for death from various causes. This relationship did not vary by country.

Review of the first study

Although the results appeared to fairly solid, I think it’s important to be critical of the results. First, we have no data that shows us whether or not coffee drinkers are just a healthier subgroup of people irrespective of their coffee drinking (they did separate out smokers from this study). Maybe coffee drinkers exercise more or eat less fats than the average person – these confounding factors have not examined carefully.

Second, like I discussed before, dose makes the poison, and dose also makes the medicine. Is there a level of coffee consumption at which point the risks outweigh the benefits? That’s not clear in this paper.

The best I could tell you from the data from this particular study of coffee health benefits is that if you’re a coffee drinker, maybe there is a slight decrease in risk of mortality, so keep on drinking. But if you don’t like coffee (yeah, there are those types around), or the caffeine effects of coffee are not to your liking, I’m not sure you should worry about suddenly taking up the habit.

Coffee health benefits – the second study

This second study, from Park et al., was also published in the Annals of Internal Medicine, once again, a very high quality journal. At a meta level, it’s as high quality as the study from Gunter et al., although this study looked at coffee consumption from a slightly different perspective.

Park et al. surveyed over 185,000 African-Americans, Native Americans, Hawaiians, Japanese-Americans, Latinos and whites, a broader ethic diversity than the first study. The researchers compared coffee consumption at various levels to a control group who drank no coffee. They adjusted for confounders such as smoking, age, alcohol intake, body mass intake, exercise, education and other factors.

For those who drank about 1 cup per day (in this case, they mean the English measurement of a cup, about 250 ml, not the standard “cup” in your local Starbucks which is about 500 ml), the HR was 0.88 or 12% reduction in total mortality. For 2-3 cups per day, the HR was 0.82. With consumption ≥ 4 cups per day, the HR was the same 0.82, or 18% reduction. All of these numbers were statistically significant.

Moreover, the researchers found that coffee increases longevity across various races.

Park et al. also found that drinking decaffeinated coffee had no effect, so you have to go for the real stuff to see these health effects.

The researchers concluded:

In summary, higher coffee consumption was associated with lower risk for all-cause death and death from heart disease, cancer, respiratory disease, stroke, diabetes, and kidney disease. Inverse associations were found in African Americans, Japanese Americans, Latinos, and whites; never-smokers, former smokers, and current smokers; those with preexisting heart disease or cancer; and healthy participants. Our findings support the recent dietary guidelines from the U.S. Department of Agriculture (33), which indicate that moderate coffee consumption can be integrated into a healthy diet and lifestyle, by confirming an inverse association with mortality and suggesting that association’s generalizability to different racial/ethnic groups.

Review of the second study

What I like about this study is that it had a better analysis of major confounders, which gives me more confidence that it’s showing a real decrease in mortality rates for coffee drinkers. Moreover, they have the semblance of a dose response which shows 3-4 cups probably gives you the best reduction in death rate, but I’d like to see much higher consumption, like 10 cups. Maybe there’s a lowered benefit as you drink more, so further research will be informative.

But I have to point out again, the reduction in mortality was, at best, 18%, which may not have any clinical significance.

Coffee health benefits – the summary

These two studies show that there is a strong biological possibility that there is some relationship between lowered mortality and coffee drinking. The European study showed that coffee lowered the risk of dying from liver disease, cancers in women, digestive diseases and circulatory disease.

Moreover, both studies showed that those who drank three or more cups a day had a lower risk for all causes of death than people who did not drink coffee.

Of course, these two studies don’t mean drinking coffee is for everyone. For some people, for example, drinking coffee can lead to serious issues such as cardiac arrhythmias. And of course, excess caffeine can lead to sleep disorders and other issues.

Finally, we don’t know what compound in coffee has this protective effect against mortality. Coffee may contain over 200 different chemicals and compounds, and it might take decades of additional research to identify what chemical (or chemicals) in coffee may provide these health benefits.

I’m going to stand by my point that I previously made. These results are interesting, but they’re not overwhelming. The large numbers in both of these studies to give credibility to the quality of the statistical analyses, but still the risk reduction from drinking coffee seems less than impressive.

I think my skepticism would be reduced if I knew what may be the contributing factor – is it that coffee drinkers are just better people? Or is it some chemical in the coffee? Maybe unhealthy people don’t drink coffee because of a physician’s recommendation, which adds bias to these studies?

So at this time, drink coffee if you like it. It may provide you with some benefit. If you shouldn’t drink coffee, or don’t like it, I don’t think there is enough evidence for you to suddenly change your habits. Coffee health benefits are intriguing, but not quite overwhelming yet.

Citations

  • Gunter MJ, Murphy N, Cross AJ, Dossus L, Dartois L, Fagherazzi G, Kaaks R, Kühn T, Boeing H, Aleksandrova K, Tjønneland A, Olsen A, Overvad K, Larsen SC, Redondo Cornejo ML, Agudo A, Sánchez Pérez MJ, Altzibar JM, Navarro C, Ardanaz E, Khaw KT, Butterworth A, Bradbury KE, Trichopoulou A, Lagiou P, Trichopoulos D, Palli D, Grioni S, Vineis P, Panico S, Tumino R, Bueno-de-Mesquita B, Siersema P, Leenders M, Beulens JWJ, Uiterwaal CU, Wallström P, Nilsson LM, Landberg R, Weiderpass E, Skeie G, Braaten T, Brennan P, Licaj I, Muller DC, Sinha R, Wareham N, Riboli E. Coffee Drinking and Mortality in 10 European Countries: A Multinational Cohort Study. Ann Intern Med. 2017 Jul 11. doi: 10.7326/M16-2945. [Epub ahead of print] PubMed PMID: 28693038.
  • Park SY, Freedman ND, Haiman CA, Le Marchand L, Wilkens LR, Setiawan VW. Association of Coffee Consumption With Total and Cause-Specific Mortality Among Nonwhite Populations. Ann Intern Med. 2017 Jul 11. doi: 10.7326/M16-2472. [Epub ahead of print] PubMed PMID: 28693036.

MSG myth – debunked with real science

msg myth

Food additives are one of the most passionate issues amongst people who eat (which would be everyone). AspartameHigh fructose corn syrup. GMO‘s. Salt. Sugar. Trans fats. Polysorbate 80. But the MSG myth is one of the most pervasive.

Of course, these additives cause angst in people because of their scary chemical names.

Obviously there is stuff, created by the beauty of natural sunlight and goddess blessed sweet waters from the alps, that is better than these man made evil chemicals. Well, no. Everything in nature is made up of “chemistry” –  25-hydroxyergocalciferol is a scary chemical name, right? Except it’s the metabolic product of the conversion of vitamin D in the human liver. It’s natural!

But let’s get back to MSG – how many times have you seen “No MSG” in a sign Chinese restaurant? Is it because China, who has been using MSG in their cuisine for centuries, has been conspiring against Americans since the first Chinese restaurant starting serving up kung pao chicken to unaware Americans?

It’s time to look at the MSG myth – is it real, or does it need a good debunking.

Continue reading “MSG myth – debunked with real science”

Benefits of omega 3 fish oil – something’s fishy

I have been skeptical of supplements for a long period of time. The supplements are generally of low quality, they don’t prevent or cure cancer, they don’t prevent colds, they can’t boost the immune system, and they don’t prevent heart disease. Now it’s the time to take a look at the benefits of omega 3 fish oil, something that is claimed by Big Supplement over and over. Is there anything there?

Unless one has a chronic disease or is chronically malnourished, there are precious few instances where supplements are necessary. A couple of cases where supplements may be critical include prenatal folic acid supplements to prevent neurological defects in the developing fetus and vitamin D supplements for individuals who do not produce enough endogenous vitamin D. However, just to keep this in perspective, excess folic acid for a long period of time may be correlated with increased rates of certain cancers.

The benefits of omega 3 fish oil has always been intriguing to me, because it is a supplement that I thought might be useful to improving health, especially cardiovascular health. Omega 3 fatty acids are generally found in fish, as it is produced by the phytoplankton that is the primary food source of much of the prey for larger fish and bio-accumulates up the food chain. However, for humans, there are other sources of omega 3 oils including walnuts and edible seeds, eggs, and other non-fish foods.

Epidemiological studies done in the late 1980s seem to indicate relatively low death rates due to cardiovascular disease in Inuit populations with high seafood consumption. These results began the rush to consume omega 3 supplements, and created a booming supplement industry.

However, since publication of those initial studies, much research has been done on seafood and heart disease. And the results don’t give much credence to the cardiovascular benefits of omega 3 fish oils as a useful supplement.

 

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GMO science – overwhelming consensus that it is safe

GMO science

Real science is hard. It takes lots of high quality evidence to support it. That evidence needs to be published in real journal. It needs to be repeated. And it has to be open to criticism and analysis. GMO science, the study of genetically modified organisms used for crops and food, shows us that GMOs are safe.

The hard work and intellectual challenges to form a scientific consensus about the safety of GMO crops and foods isn’t something that appeared out of the ether. These individuals didn’t suddenly wake up one day and proclaim from the ivory tower that GMO science says that GMOs are safe. Not even close.

Science has provided substantial evidence supporting the assertion that GMO’s are safe. GMO refusers have provided precious little evidence, save for Cherry PickingSpecial Pleading, and a few Strawman Arguments. Oh, and the occasional Poisoning the Well with the Monsanto shill accusations. Sometimes the GMO deniers will resort to the Naturalistic Fallacy that things that grow “naturally” ought to be the way foods should be – this ignores the fact that we’ve been genetically manipulating our food for ten thousand years. We’re just better at it today, but the DNA is still the DNA.

Like I said in another article, “The typical pseudoscientist will use logical fallacies to state very definitively that “it’s proven.” It’s the same whether it’s creationism (the belief that some magical being created the world some small number of years ago), alternative medicine (homeopathy, which is nothing but water, has magical properties to cure everything from cancer to male pattern baldness), or vaccine denialists. The worst problem is that in the world of the internet, if you Google these beliefs, the number of websites and hits that seem to state that they are THE TRUTH™ overwhelm those that are more skeptical or critical.”

So, using an open, but critical mind, the evidence is overwhelming – the GMO science says it’s safe for human consumption.

 

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Scientific consensus on GMO safety and climate change

scientific consensus on GMO

A scientific consensus is one of the most powerful principles in science, sitting just below the predictive power of a scientific theory. In general, a scientific consensus is the collective opinion and judgement of scientists in a particular field of study. This consensus implies general agreement, and disagreement is limited (sometimes from individuals who are not experts in the field) and considered insignificant.

This lead me to a search for the prevailing scientific consensus on GMO safety and climate change.

For clarity, the major difference between a scientific theory and a scientific consensus is that a theory is essentially considered a fact. The theory of gravity is a fact. The theory of evolution is a fact. A theory is so predictive, it is supported by so much evidence, and it is so well accepted, it would take an incredible amount of data to refute it.

The only thing that matters in forming a scientific consensus or theory is evidence. Not rhetoric. Not debate. Not opinion. Not political expediency. Not logical fallacies. Just evidence.

I’ve written about the scientific consensus on GMOs, and it is clear that nearly every independent scientific organization across the world agrees that GMOs are safe for humans and/or the environment. Moreover, most of these same organizations provide a similar consensus about climate change–ironically, there is a significant portion of people who deny one consensus but accept the other, despite the fact that the consensus for both scientific principles are based on nearly overwhelming evidence.

On the next page, I will review the statements of seven prestigious scientific organizations across the world for the scientific consensus on GMO safety and on climate change.

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Developing and supporting a scientific consensus

In my writing, I often refer to the scientific consensus, which is the collective opinion and judgement of scientists in a particular field of study. This consensus implies general agreement, though disagreement is limited and generally insignificant.

The major difference between a scientific theory and a scientific consensus is that the theory is essentially fact. It is so predictive, it is supported by so much evidence, and it is so well accepted, it takes an almost ridiculous amount of data to refute it, though it is possible.

In the hierarchy of scientific principles, we often mention scientific theories which “are large bodies of work that are a culmination or a composite of the products of many contributors over time and are substantiated by vast bodies of converging evidence. They unify and synchronize the scientific community’s view and approach to a particular scientific field.” A scientific theory is not a wild and arbitrary guess, but it is built upon a foundation of scientific knowledge that itself is based on evidence accumulated from data that resulted from scientific experimentation.

We want to focus on the scientific consensus, describing what it is. Take a deep breath, because this is a complicated one.

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High fructose corn syrup and cancer – are they related?

high fructose corn syrup and cancer

I’ve written boatloads of articles about cancer, most of which say “this or that doesn’t cause cancer,” and that “there’s only a handful of good ways to prevent it.” To be honest, if I see any news report that makes a claim that something prevents or causes cancer, I’m immediately going into full skeptic mode. Recently, I’ve seen a few stories that claim that there is a link between high fructose corn syrup and cancer, so I thought I’d dig into the science

Honestly, I don’t get the issues with high fructose corn syrup (HFCS). Part of my brain thinks that, as we’ve seen with monosodium glutamate (MSG), people just get scared of a chemical name, rather than making an evidence-based analysis of what we’re really eating. For example, “high fructose” sounds like there’s too much of evil fructose, and it will certainly cause some health problem. It must! Except, the evidence says otherwise.

I think an article by the loathsome and much ridiculed David “Avocado” Wolfe perfectly summarizes some of the pseudoscience surrounding HFCS and cancer – apparently converting corn syrup into high fructose corn syrup magically turns it into a cancer-causing poison. Now most of you will just ignore what Wolfe says about anything because he lacks any science knowledge in his writing – but maybe I reach a couple of people who saw that article and want more scientific evidence about it. Let’s look into it.

Continue reading “High fructose corn syrup and cancer – are they related?”