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An article that discusses why supplements containing large doses of antioxidants, or beta-carotene, or even vitamin megadoses  doesn't work, and can even cause harm, while eating actual foods such as fruits and vegetables has many health benefits. This is what a number of the studies I've been posting also found (especially with health benefits from eating fish and not from fish oil). go ahead and throw out the megadose supplements, and instead eat lots of fruits and vegetables. Remember fruits and vegetables contain a complex mix of nutrients and feed our microbial communities, as well as having microbes on them. From Medical Xpress:

Forget the antioxidant pills; just stick with veggies

Why just stick to eating fruits and veggies when you can get an extra boost from supplements that put good things like antioxidants into a handy pill? And that seems like it should be a good idea. If the antioxidants that occur naturally in our food, like broccoli and carrots, are good for us, a supplement with the same thing must also be good. But that's not quite true.

Antioxidants are touted as protectors of our health because they eliminate free-radicals that damage molecules in cells and tissues by grabbing electrons from them, making those molecules, in turn, unstable....On this basis, a group of scientists proposed in 1981 the creation of a nutritional supplement to fight free-radicals. They reasoned that since many observational epidemiological studies had shown that people who eat lots of vegetables are at lower risk of colon cancer, heart disease and many other bad conditions, then the "active" ingredient should be identified and put into a pill. They thought that it must be beta-carotene, which helps make carrots orange, because it's an antioxidant.

But in the late 1980s, two intervention trials, one in Seattle and the other in Finland, started....For the Seattle trial, approximately 18,000 men and women were randomized in 1988 to receive either a tablet containing beta-carotene or a tablet containing no active ingredient, which is the famous placebo. The plan was to follow the men and women for 10 years; the researchers hypothesized they would observe a lower lung cancer risk in the beta-carotene tablet group, hopefully much lower. But the opposite happened and the trial had to be stopped early because the beta-carotene group suffered significantly more cases of lung cancer than the placebo group. The same thing was seen in the Finland trial. Importantly, the amount of beta-carotene in the tablet was much higher than occurs naturally in the body in both trials.   ...continue reading "Forget the Pills, Eat the Vegetables Instead"

 People have asked me if eating sweet desserts or hamburgers is bad for the health if the rest of their diet is good - with lots of fruits, vegetables, whole grains, legumes (beans), and nuts (much like the Mediterranean diet). My sense over the past few years of looking at the research is that one should look at the overall diet, and that a "perfect diet" all the time is pretty darn hard to achieve, if not impossible, for most of us. So this new research looking at gut bacteria and "chemical fingerprints of cellular processes" (by looking at stool and urine samples) of people eating different diets (vegan, vegetarian, omnivore) was reassuring.  The findings suggest: make sure to feed your beneficial bacteria with a healthy diet like the Mediterranean diet (lots of plant-based foods), and then some deviation (cookies! steak!) is OK.

The researchers found that while the kind of gut bacteria dominating were different among the groups (vegan, vegetarian, omnivores), they also found that eating a lot of fiber-rich foods, such as fruit, vegetables, and legumes (typical of a Mediterranean diet) is linked to a rise in health promoting short chain fatty acids (SCFA). Yes, levels of trimethylamine oxide (TMAO) (which is linked to cardiovascular disease) were significantly lower in vegetarians and vegans than they were in those of the omnivores. But the more omnivores closely followed a Mediterranean diet, the lower were their TMAO levels.(Which is great!). As the researchers said: "Western omnivore diets are not necessarily detrimental when a certain consumption level of plant foods is included. From Science Daily:

High dietary fiber intake linked to health promoting short chain fatty acids

Eating a lot of fibre-rich foods, such as fruit, vegetables, and legumes--typical of a Mediterranean diet--is linked to a rise in health promoting short chain fatty acids, finds research published online in the journal Gut. And you don't have to be a vegetarian or a vegan to reap the benefits, the findings suggest.

Short chain fatty acids (SCFAs), which include acetate, propionate, and butyrate, are produced by bacteria in the gut during fermentation of insoluble fibre from dietary plant matter. SCFAs have been linked to health promoting effects, including a reduced risk of inflammatory diseases, diabetes, and cardiovascular disease.

The researchers gathered a week's information on the typical daily diet of 153 adults who either ate everything (omnivores, 51), or were vegetarians (51), or vegans (51), and living in four geographically distant cities in Italy....The Mediterranean diet is characterised by high intake of fruit, vegetables, legumes, nuts and cereals; moderately high intake of fish; regular but moderate alcohol consumption; and low intake of saturated fat, red meat, and dairy products. Most (88%) of the vegans, almost two thirds of the vegetarians (65%), and around a third (30%) of the omnivores consistently ate a predominantly Mediterranean diet.

The investigation showed distinct patterns of microbial colonisation according to usual dietary intake. Bacteroidetes were more abundant in the stool samples of those who ate a predominantly plant based diet, while Firmicutes were more abundant in those who ate a predominantly animal products diet. Both these categories of organisms (phyla) contain microbial species that can break down complex carbohydrates, resulting in the production of SCFAs.

Specifically, Prevotella and Lachnospira were more common among the vegetarians and vegans while Streptococcus was more common among the omnivores. And higher levels of SCFA were found in vegans, vegetarians, and those who consistently followed a Mediterranean dietLevels of SCFAs were also strongly associated with the quantity of fruit, vegetables, legumes, and fibre habitually consumed, irrespective of the type of diet normally eaten.

On the other hand, levels of trimethylamine oxide (TMAO)--a compound that has been linked to cardiovascular disease--were significantly lower in the urine samples of vegetarians and vegans than they were in those of the omnivores. But the more omnivores closely followed a Mediterranean diet, the lower were their TMAO levels, the analysis showed.

TMAO levels were linked to the prevalence of microbes associated with the intake of animal proteins and fat, including L-Ruminococcus (from the Lachnospiraceae family). Eggs, beef, pork and fish are the primary sources of carnitine and choline--compounds that are converted by gut microbes into trimethylamine, which is then processed by the liver and released into the circulation as TMAO.

The researchers point out that SCFA levels can naturally vary as a result of age and gender, and their study did not set out to establish any causal links. But they nevertheless suggest that the Mediterranean diet does seem to be associated with the production of health promoting SCFAs. They conclude: "We provide here tangible evidence of the impact of a healthy diet and a Mediterranean dietary pattern on gut microbiota and on the beneficial regulation of microbial metabolism towards health maintenance in the host." And they add: "Western omnivore diets are not necessarily detrimental when a certain consumption level of [plant] foods is included."

Over and over studies find that a person's diet is linked to health and diseases, and now a study finds that an unhealthy diet is linked to shrinkage of the brain, specifically the volume of the left hippocampus. The biggest effects on the hippocampus are found with both greater consumption of an unhealthy diet and lower consumption of a healthy diet.  The hippocampus is a brain structure associated with both learning and memory, as well as mood regulation, and is specifically implicated in depression. In dementia and Alzheimer's disease, the hippocampus is one of the first regions of the brain to suffer damage.

So....you want to protect your hippocampus from shrinkage. The researchers themselves  suggest that the effects may be reversible, and suggest "dietary interventions to promote hippocampal health". Once again, a healthy diet means lots of plant-based foods (for example, a Mediterranean based diet with lots of fruits, vegetables, legumes, nuts, berries, seeds), and decreasing a Western-style diet with highly processed foods, low fiber, lots of meat, fat,  and refined sugars. From Medscape:

Unhealthy Diet May Shrink the Brain

Consumption of an unhealthy Western diet characterized by meat, hamburgers, chips, and soft drinks, may reduce the volume of the left hippocampus, whereas a healthy diet of fresh vegetables and fish may increase hippocampal volume. In a study of more than 250 individuals, investigators found that during a period of 4 years, there was a difference of more than 200 cubic millimeters in hippocampal volume between individuals who ate a healthy diet and those who consumed an unhealthy diet.  ...continue reading "Shrink Your Brain With An Unhealthy Diet"

 Perhaps a nutrient deficit is associated with depression? This study found that eating a Mediterranean diet or a similar diet in which fruits, vegetables, legumes (beans), nuts, and low in processed meats is associated with lower rates of depression. From Medical Xpress:

Fruit and vegetables aren't only good for a healthy body—they protect your mind too

Eating a Mediterranean diet or other healthy dietary pattern, comprising of fruit, vegetables, legumes, and nuts and low in processed meats, is associated with preventing the onset of depression, according to research published in the open access journal BMC Medicine. A large study of 15,093 people suggests depression could be linked with nutrient deficits..

The researchers compared three diets; the Mediterranean diet, the Pro-vegetarian Dietary Pattern and Alternative Healthy Eating Index-2010. Participants used a scoring system to measure their adherence to the selected diet, i.e. the higher the dietary score indicated that the participant was eating a healthier diet. Food items such as meat and sweets (sources of animal fats: saturated and trans fatty acids) were negatively scored, while nuts, fruits and vegetables (sources of omega-3 fatty acids, vitamins and minerals respectively) were positively scored.

The study included 15,093 participants free of depression at the beginning of the study. They are former students of the University of Navarra, Spain, registered professionals from some Spanish provinces and other university graduates....Questionnaires to assess dietary intake were completed at the start of the project and again after 10 years. A total of 1,550 participants reported a clinical diagnosis of depression or had used antidepressant drugs after a median follow-up of 8.5 years.

The Alternative Healthy Eating Index-2010 was associated with the greatest reduction of risk of depression but most of the effect could be explained by its similarity with the Mediterranean Diet. Thus, common nutrients and food items such as omega-3 fatty acids, vegetables, fruits, legumes, nuts and moderate alcohol intake present in both patterns (Alternative Healthy Eating Index-2010 and Mediterranean diet) could be responsible for the observed reduced risk in depression associated with a good adherence to the Alternative Healthy Eating Index-2010.

Almudena Sanchez-Villegas says, "A threshold effect may exist. The noticeable difference occurs when participants start to follow a healthier diet. Even a moderate adherence to these healthy dietary patterns was associated with an important reduction in the risk of developing depression. However, we saw no extra benefit when participants showed high or very high adherence to the diets....This dose-response pattern is compatible with the hypothesis that suboptimal intake of some nutrients (mainly located in low adherence levels) may represent a risk factor for future depression."

Two recent meta-analyses of studies looked at depression. The first found that in 12 out of 26 studies eating fish (but NOT fish-oil supplements) was linked to lower rates of depression. The researchers hypothesize that "Fish is rich in multiple beneficial nutrients, including n-3 polyunsaturated fatty acids, high-quality protein, vitamins, and minerals." Another meta-analysis looked at dietary patterns and depression and found that a high intake of fruit, vegetables, fish, and whole grains may be associated with a reduced depression risk. From Medscape:  Fish-Rich Diet May Significantly Reduce Depression Risk

More research support for extra virgin olive oil and the Mediterranean diet being associated with anti-cancer effects, In a study conducted in Spain, women supplementing their diet with extra EVOO (extra virgin olive oil) had a lower incidence of breast cancer after about 5 years.

The Mediterranean diet stresses eating a lot of fruits, vegetables, seeds, nuts, legumes, whole grains, fish, and olive oil.

From Science Daily: Mediterranean diet plus olive oil associated with reduced breast cancer risk

Eating a Mediterranean diet supplemented with extra virgin olive oil was associated with a relatively lower risk of breast cancer in a study of women in Spain, according to an article published online by JAMA Internal Medicine.

The Mediterranean diet is known for its abundance of plant foods, fish and especially olive oil. Miguel A. Martínez-González, M.D., of the University of Navarra in Pamplona and CIBEROBN in Madrid, Spain, and coauthors analyzed the effects of two interventions with the Mediterranean diet (supplemented with extra virgin olive oil [EVOO] or nuts) compared with advice to women to follow a low-fat diet. Study participants in the two intervention groups were given EVOO (one liter per week for the participants and their families) or mixed nuts (30 grams per day: 15 grams of walnuts, 7.5 grams of hazelnuts and 7.5 grams of almonds).

From 2003 to 2009, 4,282 women (ages 60 to 80 and at high risk of cardiovascular disease) were recruited. Women were randomly assigned to the Mediterranean diet supplemented with EVOO (n=1,476), the Mediterranean diet supplemented with nuts (n=1,285) or the control diet with advice to reduce their dietary intake of fat (n=1,391). The women were an average age of 67.7 years old, had an average body mass index of 30.4, most of them had undergone menopause before the age of 55 and less than 3 percent used hormone therapy. During a median follow-up of nearly five years, the authors identified 35 confirmed incident (new) cases of malignant breast cancer.

The authors report that women eating a Mediterranean diet supplemented with EVOO showed a 68 percent relatively lower risk of malignant breast cancer than those allocated to the control diet. Women eating a Mediterranean diet supplemented with nuts showed a nonsignificant risk reduction compared with women in the control group.

The authors note a number of limitations in their study including that breast cancer was not the primary end point of the trial for which the women were recruited; the number of observed breast cancer cases was low; the authors do not have information on an individual basis on whether and when women in the trial underwent mammography; and the study cannot establish whether the observed beneficial effect was attributable mainly to the EVOO or to its consumption within the context of the Mediterranean diet. [The original study.]

New research has found that low vitamin D levels among older adults is associated with accelerated cognitive decline and impaired performance (particularly in areas of memory and executive function). The next research in this area will have to look at whether vitamin D supplementation will change (slow down) the decline. Please note that it is widely accepted that an average daily intake of 1000 IU  of D3 daily is safe. The best source of  vitamin D is sunlight. From Science Daily:

Low vitamin D among elderly associated with decline in cognition, dementia

Vitamin D insufficiency among the elderly is highly correlated with accelerated cognitive decline and impaired performance, particularly in domains such as memory loss that are associated with Alzheimer's disease and dementia, researchers with the UC Davis Alzheimer's Disease Center and Rutgers University have found. The effect is "substantial," with individuals with low vitamin D declining at a rate three times faster than those with adequate vitamin D levels

The researchers said their findings amplify the importance of identifying vitamin D insufficiency among the elderly, particularly high-risk groups such as African-Americans and Hispanics, who are less able to absorb the nutrient from its most plentiful source: sunshine. Among those groups and other darker-skinned individuals, low vitamin D should be considered a risk factor for dementia, they said. "Independent of race or ethnicity, baseline cognitive abilities and a host of other risk factors, vitamin D insufficiency was associated with significantly faster declines in both episodic memory and executive function performance," said Joshua Miller...

The large, longitudinal study was conducted in nearly 400 racially and ethnically diverse men and women in Northern California participating in longitudinal research at the Alzheimer's Disease Center in Sacramento, Calif. Fifty percent of participants were Caucasian and 50 percent were African-American or Hispanic. The participants had a mean age of 76 and were either cognitively normal, had mild cognitive impairment, or dementia.The participants' serum vitamin D status was measured at the beginning of the study.... Overall, 26 percent were deficient and 35 percent were insufficient. Among Caucasians, 54 percent had low vitamin D, compared with 70 percent of African-Americans and Hispanics.

Over five years of follow-up, vitamin D deficient individuals experienced cognitive declines that were two-to-three times faster than those with adequate serum vitamin D levels. In other words it took only two years for the deficient individuals to decline as much as their counterparts with adequate Vitamin D declined during the five-year follow-up period.

Exposing the skin to sunlight is the major source of vitamin D. Racial and some ethnic minorities are at greater risk of low vitamin D because the higher concentration of melanin that makes their skin darker -- and protects against skin cancer in sunny climates -- also inhibits synthesis of vitamin D. Diet is the other major source of vitamin D. Dietary vitamin D is obtained particularly through dairy consumption. The intake of dairy products is especially low among minority groups, with only 6.5 percent of African-Americans and 11 percent of Mexican-Americans nationwide consuming the recommended three daily servings of dairy products, the study says.

Image result for dark chocolate So far all the studies I've seen in the past 2 years about cocoa and chocolate have found various beneficial health effects from regularly eating small amounts of cocoa and chocolate. Now 2 new studies found benefits from the flavanols found in cocoa beans and chocolate. The studies found that consuming cocoa flavanols lowers blood pressure, increases flow-mediated vasodilation,improves blood cholesterol profile, and that regular dietary intake may reduce the risk of cardiovascular disease (CVD). However, note that chocolate and cocoa contain other compounds besides flavanols and these may also be exerting positive effects.

So now the question becomes, which chocolates have high levels of flavanols? Modern processing removes some of the flavanols - in fact, the more it undergoes processing, the more flavanols are lost. But it appears that dark chocolate and cocoa that has not undergone Dutch processing is best. According to a Medscape article on cocoa flavanols: "Traditional processing methods that yield "modern chocolate," especially alkalinization (dutching or Dutch processing, to mellow flavor), strips flavanols from cocoa. The bitterness from cacao mostly comes from flavanols. With the emerging recognition of the beneficial effects of flavanols there has been a shift in commercial production towards chocolate forms with high flavanol content." A recent study by Consumer Lab, which compared flavanol levels across many cocoa and chocolate products, also found that some chocolate brands were contaminated with cadmium (a toxic heavy metal), but that cocoa nibs had significantly lower levels. At any rate, the medical evidence does not support gorging on chocolate, but instead consuming chocolate or cocoa in moderation. From Science Daily:

Cocoa flavanols lower blood pressure and increase blood vessel function in healthy people

Two recently published studies in the journals Age and the British Journal of Nutrition (BJN) demonstrate that consuming cocoa flavanols improves cardiovascular function and lessens the burden on the heart that comes with the aging and stiffening of arteries. The studies also provide novel data to indicate that intake of cocoa flavanols reduces the risk of developing cardiovascular disease (CVD).

As we age, our blood vessels become less flexible and less able to expand to let blood flow and circulate normally, and the risk of hypertension also increases. Arterial stiffness and blood vessel dysfunction are linked with cardiovascular disease -- the number one cause of deaths worldwide....Cocoa flavanols are plant-derived bioactives from the cacao bean. Dietary intake of flavanols has been shown to have a beneficial effect on cardiovascular health but the compounds are often destroyed during normal food processing. Earlier studies have demonstrated that cocoa flavanol intake improves the elasticity of blood vessels and lowers blood pressure....These two studies in Age and BJN are the first to look at the different effects dietary cocoa flavanols can have on the blood vessels of healthy, low-risk individuals with no signs or symptoms of cardiovascular disease.

Cocoa flavanols increase blood vessel flexibility and lower blood pressure - In the study published in Age, two groups of 22 young (<35 years of age) and 20 older (50-80 years of age) healthy men consumed either a flavanol-containing drink, or a flavanol-free control drink, twice a day for two weeks. The researchers then measured the effect of flavanols on hallmarks of cardiovascular aging, such as arterial stiffness (as measured by pulse wave velocity), blood pressure and flow-mediated vasodilation (the extent to which blood vessels dilate in response to nitric oxide). They found that vasodilation was significantly improved in both age groups that consumed flavanols over the course of the study (by 33% in the younger age group and 32% in the older age group over the control intervention). In the older age group, a statistically and clinically significant decrease in systolic blood pressure of 4 mm Hg over control was also seen.

Improving cardiovascular health and lowering the risk of CVD - In the second study, published in BJN, the researchers extended their investigations to a larger group (100) of healthy middle-aged men and women (35-60 years) with low risk of CVD. The participants were randomly and blindly assigned into groups that consumed either a flavanol-containing drink or a flavanol-free control drink, twice a day for four weeks.

"We found that intake of flavanols significantly improves several of the hallmarks of cardiovascular health," says Professor Kelm. In particular, the researchers found that consuming flavanols for four weeks significantly increased flow-mediated vasodilation by 21%. Increased flow-mediated vasodilation is a sign of improved endothelial function and has been shown by some studies to be associated with decreased risk of developing CVD. In addition, taking flavanols decreased blood pressure (systolic by 4.4 mmHg, diastolic by 3.9 mmHg), and improved the blood cholesterol profile by decreasing total cholesterol (by 0.2 mmol/L), decreasing LDL cholesterol (by 0.17 mmol/L), and increasing HDL cholesterol (by 0.1 mmol/L).

The researchers also calculated the Framingham Risk Score -- a widely used model to estimate the 10-year cardiovascular risk of an individual -- and found that flavanol intake reduced the risk of CVD. "Our results indicate that dietary flavanol intake reduces the 10-year risk of being diagnosed with CVD by 22% and the 10-year risk of suffering a heart attack by 31%," says Professor Kelm.

The combined results of these studies demonstrate that flavanols are effective at mitigating age-related changes in blood vessels, and could thereby reduce the risk of CVD in healthy individuals. The application of 10-year Framingham Risk Scores should be interpreted with caution as the duration of the BJN study was weeks not years and the number of participants was around 100, not reaching the scale of the Framingham studies. That being said, Professor Kelm comments that "the reduction seen in risk scores suggests that flavanols may have primary preventive potential for CVD."

The following studies reinforce the advice that people should eat a variety of fruits and vegetables, as well as olive oil (part of the Mediterranean diet).

Studies find that consumption of fruits, vegetables, herbs, and extra virgin olive oil have various health benefits, and the following studies, even though not done with humans, suggest some reasons for their health benefits.

Luteolin appears to have anti-tumor effects, and so may reduce cancer risk. Dietary sources of luteolin include celery, broccoli, green pepper, parsley, thyme, dandelion, perilla, chamomile tea, carrots, olive oil, peppermint, rosemary, navel oranges, and oregano. Extra-virgin olive oil contains the ingredient oleocanthal, which appears to kill a variety of human cancer cells without harming healthy cells.

From Science Daily: Natural compound could reduce breast cancer risk in some women

The odds of women being diagnosed with breast cancer increase in postmenopausal women who have taken a combined estrogen and progestin hormone replacement therapy; these women also have an increased risk of developing progestin-accelerated breast tumors. Now, researchers have found that luteolin, a natural compound found in herbs such as thyme and parsley as well as vegetables such as celery and broccoli, could reduce the cancer risk for women who have taken hormone replacement therapy.

 "Nevertheless, research has proven that a higher incidence of breast cancer tumors can occur in women receiving therapies that involve a combination of the natural component estrogen and the synthetic progestin. Most older women normally have benign lesions in breast tissue," Hyder said. "These lesions typically don't form tumors until they receive the 'trigger'-- in this case, progestin--that attracts blood vessels to cells essentially feeding the lesions causing them to expand." His newest study shows that when the supplement luteolin is administered to human breast cancer cells in the lab, benefits can be observed including the reduction of those vessels "feeding" the cancer cells causing cancer cell death.

.... the natural compound exerts its anti-tumor effects in a variety of ways. Then, Hyder further tested laboratory mice with breast cancer and found that blood vessel formation and stem cell-like characteristics also were reduced in vivo, or inside the body.

From Medical Xpress: Ingredient in olive oil kills cancer cells with their own enzymes

A Rutgers nutritional scientist and two cancer biologists at New York City's Hunter College have found that an ingredient in extra-virgin olive oil kills a variety of human cancer cells without harming healthy cells. The ingredient is oleocanthal, a compound that ruptures a part of the cancerous cell, releasing enzymes that cause cell death.

Paul Breslin, professor of nutritional sciences in the School of Environmental and Biological Sciences, and David Foster and Onica LeGendre of Hunter College, report that oleocanthal kills cancerous cells in the laboratory by rupturing vesicles that store the cell's waste....Scientists knew that oleocanthal killed some cancer cells, but no one really understood how this occurred. Breslin believed that oleocanthal might be targeting a key protein in cancer cells that triggers a programmed cell death, known as apoptosis....  

After applying oleocanthal to the cancer cells, Foster and LeGendre discovered that the cancer cells were dying very quickly – within 30 minutes to an hour....LeGendre, a chemist, provided the answer: The cancer cells were being killed by their own enzymes. The oleocanthal was puncturing the vesicles inside the cancer cells that store the cell's waste – the cell's "dumpster," as Breslin called it, or "recycling center," as Foster refers to it. These vesicles, known as lysosomes are larger in cancer cells than in healthy cells, and they contain a lot of waste. But oleocanthal didn't harm healthy cells, the researchers found. It merely stopped their life cycles temporarily – "put them to sleep," Breslin said. After a day, the healthy cells resumed their cycles.  

A nice summary article about the benefits and risks of coffee consumption. Summary of effects of drinking coffee1) May potentially increase blood pressure, but also may lower the risk for coronary disease, and protect against heart disease. 2) May cut stroke risk by as much as 25%, 3) Linked to  improved glucose metabolism, reduced risk for type 2 diabetes, and promotion of weight loss in overweight patients. 4) May reduce the risk for several cancers. 5) Appears to slow the progression of dementia and Parkinson's disease. 6) A significantly decreased risk of developing depression. 7) Slows progression in alcoholic cirrhosis, hepatitis C, and NAFLD (non-alcoholic fatty liver disease). 8) May be beneficial in dry-eye syndrome, gout, and in preventing MRSA infection. 9) May increase blood pressure, anxiety, insomnia, tremor, withdrawal symptoms, and potential increased risk of glaucoma. From Medscape:

How Healthy Is Coffee? The Latest Evidence

Earlier this year, the Dietary Guidelines Advisory Committee (DGAC) released a report[1] stating that up to five cups of coffee per day, or up to 400 mg of caffeine, is not associated with long-term health risks. Not only that, they highlighted observational evidence that coffee consumption is associated with reduced risk for several diseases, including type 2 diabetes, cardiovascular disease (CVD), and neurodegenerative disorders. The body of data suggesting that moderate coffee—and, in all likelihood, tea—consumption is not only safe but beneficial in a variety of mental and medical conditions is growing fast.

A 2012 study of over 400,000 people, published in the New England Journal of Medicine, reported that coffee consumption is associated with a 10% reduction in all-cause mortality at 13-year follow-up.... It's important to note that much of the evidence on the potential health effects of coffee, caffeine, and other foods and nutrients is associational and doesn't prove causality—observational investigations come with limitations and often rely on error-prone methods such as patient questionnaires. However, the sheer volume of existing observational data linking coffee and/or caffeine with various health benefits—as well as, in many cases, evidence of a dose response—suggests that the most widely consumed stimulant in the world has positive influences on our health. 

Cardiovascular Disease:...However, when caffeine is ingested via coffee, enduring blood pressure elevations are small and cardiovascular risks may be balanced by protective properties. Coffee beans contain antioxidant compounds that reduce oxidation of low-density lipoprotein (LDL) cholesterol, and coffee consumption has been associated with reduced concentrations of inflammatory markers. Moderate coffee intake is associated with a lower risk for coronary heart disease as far out as 10 years, and data suggest that an average of two cups per day protects against heart failure.

Cerebrovascular Disease and Stroke: The vascular benefits of coffee are not lost on the brain. According to a 2011 meta-analysis, consuming between one and six cups per day reportedly cut stroke risk by 17%. A 22%-25% risk reduction was seen in a large sample of Swedish women followed for an average of 10 years.

Diabetes:...Numerous studies have linked regular coffee drinking with improved glucose metabolism, insulin secretion, and a significantly reduced risk for diabetes. Most recently, findings from a long-term study published this year suggest that coffee drinkers are roughly half as likely to develop type 2 diabetes as are nonconsumers, even after accounting for smoking, high blood pressure, and family history of diabetes.

Cancer: ...Evidence suggests that moderate to heavy coffee consumption can reduce the risk for numerous cancers, including endometrial (> 4 cups/day), prostate (6 cups/day), head and neck (4 cups/day), basal cell carcinoma (> 3 cups/day), melanoma,and breast cancer (> 5 cups/day). The benefits are thought to be at least partially due to coffee's antioxidant and antimutagenic properties.

Neurodegeneration: Beyond the short-term mental boost it provides, coffee also appears to benefit longer-term cognitive well-being. A 2012 study reported that patients with mild cognitive impairment and plasma caffeine levels of > 1200 ng/mL—courtesy of approximately three to five cups of coffee per day—avoided progression to dementia over the following 2-4 years. On a related note, a study from last year reported that caffeine consumption appears to enhance memory consolidation....Caffeinated coffee has long been thought to be neuroprotective in Parkinson disease (PD)....—as well as in multiple sclerosis

Depression: A 2011 study suggests that a boost in coffee consumption might also benefit our mental health: Women who drank two to three cups of coffee per day had a 15% decreased risk for depression compared with those who drank less than one cup per week. A 20% decreased risk was seen in those who drank four cups or more per day. Newer work also suggests that regular coffee drinking may be protective against depression.

Liver Disease: The liver might help break down coffee, but coffee might protect the liver (in some cases). Evidence suggests that coffee consumption slows disease progression in patients with alcoholic cirrhosis and hepatitis C, and reduces the risk of developing hepatocellular carcinoma. A 2012 study reported that coffee intake is associated with a lower risk for nonalcoholic fatty liver disease (NAFLD), while work published in 2014 found that coffee protects against liver fibrosis in those with already established NAFLD.

And That's Not All…: An assortment of other research suggests that coffee intake might also relieve dry-eye syndrome by increasing tear production, reduce the risk for gout, and potentially fight infection. Coffee and hot tea consumption were found to be protective against one of the medical community's most concerning bugs, methicillin-resistant Staphylococcus aureus (MRSA). While it remains unclear whether the beverages have systemic antimicrobial activity, study participants who reported any consumption of either were approximately half as likely to have MRSA in their nasal passages.

And Finally, the Risks: As is often the case, with benefits come risks, and coffee consumption certainly has negative medical and psychiatric effects to consider. Besides the aforementioned potential increase in blood pressure, coffee can incite or worsen anxiety, insomnia, and tremor and potentially elevate glaucoma risk. Also, given the potential severity of symptoms, caffeine withdrawal syndrome is included as a diagnosis in the DSM-5.

Once again, a study finds that a supplement has no benefit - here omega-3 supplements did not slow cognitive decline in older adults. On the other hand, studies find that eating foods with omega-3 fatty acids (such as fish) has beneficial health effects. Regular consumption of fish is associated with lower rates of age-related macular degeneration (AMD), cardiovascular disease, and possibly dementia.  From Science Daily:

No benefit of omega-3 supplements for cognitive decline, study shows

While some research suggests that a diet high in omega-3 fatty acids can protect brain health, a large clinical trial by researchers at the National Institutes of Health found that omega-3 supplements did not slow cognitive decline in older persons. With 4,000 patients followed over a five-year period, the study is one of the largest and longest of its kind.

Dr. Chew leads the Age-Related Eye Disease Study (AREDS), which was designed to investigate a combination of nutritional supplements for slowing age-related macular degeneration (AMD), a major cause of vision loss among older Americans. That study established that daily high doses of certain antioxidants and minerals -- called the AREDS formulation -- can help slow the progression to advanced AMD.

A later study, called AREDS2, tested the addition of omega-3 fatty acids to the AREDS formula. But the omega-3's made no difference. Omega-3 fatty acids are made by marine algae and are concentrated in fish oils; they are believed to be responsible for the health benefits associated with regularly eating fish, such as salmon, tuna, and halibut.* Where studies have surveyed people on their dietary habits and health, they've found that regular consumption of fish is associated with lower rates of AMD, cardiovascular disease, and possibly dementia. "We've seen data that eating foods with omega-3 may have a benefit for eye, brain, and heart health," Dr. Chew explained.

Omega-3 supplements are available over the counter and often labeled as supporting brain health. A large 2011 study found that omega-3 supplements did not improve the brain health of older patients with preexisting heart disease.

With AREDS2, Dr. Chew and her team saw another opportunity to investigate the possible cognitive benefits of omega-3 supplements, she said. All participants had early or intermediate AMD. They were 72 years old on average and 58 percent were female....Participants were given cognitive function tests at the beginning of the study to establish a baseline, then at two and four years later.... The cognition scores of each subgroup decreased to a similar extent over time, indicating that no combination of nutritional supplements made a difference.

* Other omega-3 fatty acids are found in plant foods such as flaxseed, walnuts, soy products, and canola and soybean oils. Specific omega-3 fatty acids from these sources were not studied.