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Category: nutrition

Published on Leave a comment on Vitamin D, Breast Cancer, and Melanoma

Two more studies found that higher levels of vitamin D in the blood are associated with better health outcomes - one study found a lower risk of breast cancer, especially among postmenopausal women, and in the other - better outcomes after a metastatic melanoma diagnosis.

The breast cancer study suggested that a fairly high blood level of vitamin D (25(OH)D serum level>38.0 ng/mL) was associated with a lower risk of breast cancer. But overall they found that women supplementing with vitamin D (more than 4 times a week) at any dose had a lower risk of breast cancer over a 5 year period than those not supplementing with vitamin D. From Environmental Health Perspectives:

Serum Vitamin D and Risk of Breast Cancer within Five Years

Vitamin D is an environmental and dietary agent with known anticarcinogenic effects, but protection against breast cancer has not been established. We evaluated the association between baseline serum 25-hydroxyvitamin D [25(OH)D] levels, supplemental vitamin D use, and breast cancer incidence over the subsequent 5 y of follow-up. From 2003-2009, the Sister Study enrolled 50,884 U.S. women 35-74 y old who had a sister with breast cancer but had never had breast cancer themselves. Using liquid chromatography-mass spectrometry, we measured 25(OH)D in serum samples from 1,611 women who later developed breast cancer and from 1,843 randomly selected cohort participants.

We found that 25(OH)D levels were associated with a 21% lower breast cancer hazard (highest versus lowest quartile). Analysis of the first 5 y of follow-up for all 50,884 Sister Study participants showed that self-reported vitamin D supplementation was associated with an 11% lower hazard. These associations were particularly strong among postmenopausal women.

In this cohort of women with elevated risk, high serum 25(OH)D levels and regular vitamin D supplement use were associated with lower rates of incident, postmenopausal breast cancer over 5 y of follow-up. These results may help to establish clinical benchmarks for 25(OH)D levels; in addition, they support the hypothesis that vitamin D supplementation is useful in breast cancer prevention.

The first sentence in the melanoma study lays out what is widely known: "Vitamin D deficiency (≤20 ng/mL) is associated with an increased incidence and worse prognosis of various types of cancer including melanoma." Studies show that the relationship between vitamin D, sunlight exposure, and melanoma is complicated in a number of ways, including: sun exposure may be associated with increased survival in patients with melanoma. which may mean that vitamin D has a protective role in patients with melanoma. Several studies suggest that vitamin D may delay melanoma recurrence and improve overall prognosis. The study also found that metastatic melanoma patients with vitamin D deficiency who are unable to or don't raise their vitamin D blood levels (25(OH)D3) have a worse outcome compared to those who are are able to markedly increase (by greater than >20 ng/mL) their 25(OH)D3 levels. From Oncotarget:

Vitamin D deficiency is associated with a worse prognosis in metastatic melanoma

Vitamin D deficiency (≤20 ng/mL) is associated with an increased incidence and worse prognosis of various types of cancer including melanoma. A retrospective, single-center study of individuals diagnosed with melanoma from January 2007 through June 2013 who had a vitamin D (25(OH)D3) level measured within one year of diagnosis was performed to determine whether vitamin D deficiency and repletion are associated with melanoma outcome.

A total of 409 individuals diagnosed with histopathology-confirmed melanoma who had an ever measured serum 25(OH)D3 level were identified. 252 individuals with a 25(OH)D3 level recorded within one year after diagnosis were included in the study .... A worse melanoma prognosis was associated with vitamin D deficiency, higher stage, ulceration, and higher mitotic rate. In patients with stage IV metastatic melanoma, vitamin D deficiency was associated with significantly worse melanoma-specific mortality. Patients with metastatic melanoma who were initially vitamin D deficient and subsequently had a decrease or ≤20 ng/mL increase in their 25(OH)D3 concentration had significantly worse outcomes compared to non-deficient patients who had a >20 ng/mL increase. Our results suggest that initial vitamin D deficiency and insufficient repletion is associated with a worse prognosis in patients with metastatic melanoma.

Published on Leave a comment on Which Form of Vitamin D to Take?

I've frequently mentioned that when taking vitamin D supplements, the one to take is vitamin D3, and not D2. Medscape (the medical site) has an article explaining that results of a recent study showed that vitamin D3 is twice as effective as D2 in raising blood levels of vitamin D. The vitamin D3 form is derived from animal products, while vitamin D2 is plant-based. So check any supplements you purchase because many contain the vitamin D2 form of vitamin D.

Of course, sunlight is the best because it has more benefits than vitamin D - such as also having low levels of "blue light" which energizes T cells (which are part of the immune system). From Medscape:

Vitamin D3, Not D2, Is Key to Tackling Vitamin D Deficiency

Vitamin D3 is significantly more effective at raising the serum biological marker of vitamin D status than vitamin D2 when given at standard doses in everyday food and drink, say UK researchers — findings that could have major implications for both current guidelines and the supplement industry.

In a randomized controlled trial of vitamin D supplements, vitamin D3, which is derived from animal products, was associated with significantly higher serum total 25-hydroxyvitamin D [25(OH)D] levels after 12 weeks than vitamin D2, which is plant-based and currently used in the vast majority of vitamin D supplements.

"The importance of vitamin D in our bodies is not to be underestimated, but living in the UK it is very difficult to get sufficient levels from its natural source, the sun, so we know it has to be supplemented through our diet," explained lead author Laura Tripkovic, PhD, department of nutritional sciences, University of Surrey, Guildford, United Kingdom, in a press release.

She added, "Our findings show that vitamin D3 is twice as effective as D2 in raising vitamin D levels in the body, which turns current thinking about the two types of vitamin D on its head." "Those who consume D3 through fish, eggs, or vitamin D3-containing supplements are twice as likely to raise their vitamin D status [compared with those] consuming vitamin D2 rich foods, such as mushrooms, vitamin D2 fortified bread, or vitamin D2 containing supplements, helping to improve their long-term health." [Original study.]

Published on Leave a comment on More Concerns With Nanoparticles In Foods

 The use of nanoparticles in foods is increasing every year, but we still know very little about whether they have health risks to humans, especially if one is eating foods with them daily (thus having chronic exposure). The nanoparticles in foods are ingredients so small that they are measured in nanometers or billionths of one meter. The most common nanoingredients are: titanium dioxide, silicon dioxide, and zinc oxide.

Titanium dioxide is typically used as a "food coloring" to make foods whiter or brighter, but it may or may not be listed on the label. In Europe, this food additive is known as E171. Currently there are no restrictions on using titanium diaoxide nanoparticles in food.

Recent search suggests that there may be health effects from the nanoparticles in our food (here and here), thus we should be cautious. Evidence is accumulating that titanium dioxide nanoparticles can have a negative inflammatory effect on the intestinal lining.

Similarly, a new study  looking at both mice and humans suggests that individuals with inflammatory intestinal conditions such as intestinal bowel disease (colitis and Crohn's disease) might have negative health effects from titanium dioxide nanoparticles - that they could worsen intestinal inflammation. Interestingly, the nanoparticles accumulated in spleens of mice used in the study. The researchers also found that levels of titanium were increased in the blood of patients with active colitis. From Science Daily:

Titanium dioxide nanoparticles can exacerbate colitis

Titanium dioxide, one of the most-produced nanoparticles worldwide, is being used increasingly in foodstuffs. When intestinal cells absorb titanium dioxide particles, this leads to increased inflammation and damage to the intestinal mucosa in mice with colitis. Researchers at the University of Zurich recommend that patients with colitis should avoid food containing titanium dioxide particles. The frequency of inflammatory bowel disease like Crohn's disease and ulcerative colitis has been on the rise in many Western countries for decades.... In addition to genetic factors, environmental factors like the Western lifestyle, especially nutrition, play an essential role in the development of these chronic intestinal diseases.

The research of Gerhard Rogler, professor of gastroenterology and hepatology at the University of Zurich, now shows that titanium dioxide nanoparticles can intensify the inflammatory reaction in the bodies of patients with inflammatory intestinal diseases. Titanium dioxide is a white pigment used in medicines, cosmetics and toothpaste and increasingly as food additive E171, for example, in icing, chewing gum or marshmallows. Until now, there have been no restrictions on its use in the food industry.

The scientists led by Gerhard Rogler concentrated their research on a protein complex inside cells: the NLRP3 inflammasome. This protein complex is part of the non-specific immune system, which detects danger signals and then triggers inflammation. If the inflammasome is activated by bacterial components, for example, and the inflammatory reaction plays a vital role in the defense against infective agents. In the same way, NLRP3 can be activated by small inorganic particles -- sometimes with negative consequences: If uric acid crystals form in the cells, for example the inflammation leads to gout.

The research team first studied the effect of inorganic titanium dioxide particles in cell cultures. They were able to show that titanium dioxide can penetrate human intestinal epithelial cells and macrophages and accumulate there. The nanoparticles were detected as danger signals by inflammasomes, which triggered the production of inflammatory messengers. In addition, patients with ulcerative colitis, whose intestinal barrier is disrupted, have an increased concentration of titanium dioxide in their blood. "This shows that these particles can be absorbed from food under certain disease conditions," Rogler says.

In a further step, the scientists orally administered titanium dioxide nanoparticles to mice, which serve as a disease model for inflammatory bowel disease. Here, as well, the particles activated the NLRP3 complex, which led to strong intestinal inflammation and greater damage to the intestinal mucosa in the mice. In addition, titanium dioxide crystals accumulated in the animals' spleens. Whether these findings will be confirmed in humans must now be determined in further studies. "Based on our results," Rogler concludes, "patients with an intestinal barrier dysfunction as found in colitis should abstain from foods containing titanium dioxide."  [Original study.]

Published on Leave a comment on Common Chemicals Linked to Chronic Diseases

Another study was just published with worrisome findings about phthalates. Phthalates are a group of chemicals used widely in common consumer products such as food packaging, toys, medical devices, medications, and personal care products. They are endocrine disruptors (can interfere with normal hormonal function) and are linked to a number of health problems (here, here, and here).

The study looked at urban Australian men and found that the higher the level of phthalates, the higher the rate of cardiovascular disease, type-2 diabetes, and hypertension. The researchers also found that higher levels of chronic low-grade inflammatory biomarkers (meaning higher levels of low-grade inflammation) was associated with higher levels of phthalates. All these findings confirm what other studies, done in other countries, have found.

Phthalates, which are measured in the urine,  were detected in 99.96% of the 1504 men. Eating a western dietary pattern (fast food, highly processed, low fiber) was also associated with higher phthalate levels.  However, they did not find an association of phthalate levels with asthma and depression. From Science Daily:

Everyday chemicals linked to chronic disease in men

Chemicals found in everyday plastics materials are linked to cardiovascular disease, type-2 diabetes and high blood pressure in men, according to Australian researchers. Researchers from the University of Adelaide and the South Australian Health and Medical Research Institute (SAHMRI) investigated the independent association between chronic diseases among men and concentrations of potentially harmful chemicals known as phthalates.

Phthalates are a group of chemicals widely used in common consumer products, such as food packaging and wrappings, toys, medications, and even medical devices. Researchers found that of the 1500 Australian men tested, phthalates were detected in urine samples of 99.6% of those aged 35 and over. "We found that the prevalence of cardiovascular disease, type-2 diabetes and high blood pressure increased among those men with higher total phthalate levels," says senior author Associate Professor Zumin Shi, from the University of Adelaide's Adelaide Medical School and the Freemasons Foundation Centre for Men's Health, and a member of SAHMRI's Nutrition & Metabolism theme.

"While we still don't understand the exact reasons why phthalates are independently linked to disease, we do know the chemicals impact on the human endocrine system, which controls hormone release that regulate the body's growth, metabolism, and sexual development and function. "In addition to chronic diseases, higher phthalate levels were associated with increased levels of a range of inflammatory biomarkers in the body," he says.

Age and western diets are directly associated with higher concentrations of phthalates. Previous studies have shown that men who ate less fresh fruit and vegetables and more processed and packaged foods, and drank carbonated soft drinks, have higher levels of phthalates in their urine.... Associate Professor Shi says that although the studies were conducted in men, the findings are also likely to be relevant to women. "While further research is required, reducing environmental phthalates exposure where possible, along with the adoption of healthier lifestyles, may help to reduce the risk of chronic disease," he says. [Original study.]

Published on Leave a comment on Drinking Coffee May Reduce Risk of Death

Once again several studies found health benefits associated with drinking coffee daily - this time "reduced risk of death" in 2 studies, and in one study a reduced risk of gallbladder cancer.

Just keep in mind that the studies found associations, but did not establish that drinking coffee caused X (reduced risk of death) - so perhaps coffee drinkers differ in some still unknown way from non-coffee drinkers. But...so many studies are piling up showing an association with health benefits that it looks likely that it is actually the coffee causing the benefits. Both decaffeinated and regular coffee seem beneficial, and it doesn't matter how it is prepared (e.g., espresso, drip, cappuccino). (Earlier posts about coffee - here, here, here)

In the one study higher consumption of coffee was associated with a lower risk of death from heart disease, cancer, stroke, diabetes, and kidney disease in African Americans, Japanese Americans, Latinos, and whites. People who consumed a cup of coffee a day (decaffeinated or regular) were 12 percent less likely to die compared to those who didn't drink coffee, and those who drank two to three cups a day had an 18 percent reduced chance of death.

The conclusion of the other study of over half million adults in 10 European countries was similar: coffee drinking was associated with lower risk for death from "all causes", especially from circulatory diseases and diseases related to the digestive tract. This association held up among all the countries. The highest levels of consumption  group (3 cups or more of coffee per day)  had the lowest risk of death - as compared to those drinking none or less than 1 cup of coffee per day. However, the one negative result from drinking more than 3 cups of coffee daily was an increase in risk for ovarian cancer mortality in women (but only when compared to coffee non-drinkers).

From STAT News: Drink coffee? It won’t hurt you, and may reduce your risk of an early death

Good news, coffee drinkers: A couple of massive new studies that looked at hundreds of thousands of people for about 16 years finds that a few cups of coffee a day won’t hurt you and could lower your risk of dying prematurely. The studies reinforce previous findings that drinking an 8-ounce cup of joe (or three) won’t hurt you, but the authors of the new works and other experts say caveats abound.

Murphy told STAT his is the largest study on coffee and mortality to date. In the study, researchers with the WHO’s International Agency for Research on Cancer and Imperial College London tracked 521,000 adults from 10 European countries who self-reported their coffee consumption over an average of 16 years.... In investigating more than 40,000 deaths from this group, the team found that participants who fell into the highest 25 percent of coffee consumers had a lower risk of death due to any cause compared to non-coffee drinkers. They saw a reduced risk of early death by diseases related to the digestive and circulatory systems. The researchers also discovered a link between higher coffee consumption and lower risk of early death by lung cancer in men. And they also looked at suicide — completed suicides were lower for coffee drinkers, but only in men. [Original study.]

In a second study of 180,000 people tracked for an average of 16 years, University of Southern California investigators found drinking one to six cups of coffee per week led to a decreased risk of early death. The study was focused on non-white populations, andtheir findings proved consistent for coffee drinkers across racial and ethnic groups. One of the USC study’s senior authors, V. Wendy Setiawan... said coffee consumption may be linked a lower risk of early death for people with heart disease, cancer, chronic lower respiratory disease, stroke, and kidney disease.Drink one cup per day, and the risk of dying early from those diseases decreases by 12 percent, she said. [Original study.]

This 2016 study is from Medscape: Coffee Consumption and Risk of Gallbladder Cancer in a Prospective Study

Evidence indicates that coffee consumption may reduce the risk of gallstone disease, which is strongly associated with increased risk of gallbladder cancer. The association between coffee consumption and gallbladder cancer incidence was examined in a prospective cohort study of 72,680 Swedish adults (aged 45 − 83 years) who were free of cancer and reported their coffee consumption at baseline.....  In conclusion, coffee consumption was observed to be associated with a reduced risk of gallbladder cancer. A potential protective association between coffee consumption and risk of gallbladder cancer may be mediated via reduced gallstone formation or through other mechanisms such as reduction of oxidative damage and inflammation and regulation of DNA repair, phase II enzymatic activity, apoptosis, angiogenesis, and metastasis.

Published on Leave a comment on Is Olive Oil Good For The Aging Brain?

Lately more and more research has been finding health benefits with frequent consumption of extra virgin olive oil (EVOO). It is also a basic part of the popular Mediterranean diet - which emphasizes fresh fruits and vegetables, nuts, legumes (beans), whole grains, some fish, and extra virgin olive oil. Now a study conducted by investigators at Temple University in Philadelphia, Pennsylvania, suggests that the olive oil in the Mediterranean diet probably promotes healthy brain aging. The researchers said: "Our study is the first demonstration that EVOO can beneficially affect memory, amyloid plaques, and tau pathology, the hallmark lesions in the brain of Alzheimer's patients."

But... note that they are taking findings from their study done on mice and hypothesizing that this is what is also going on in humans.  Their study used specially bred mice (and only 22 in total) - one group which received extra virgin olive oil in their food (starting at 6 months of age), and the other not. The researchers found that after a few months of this diet that there were differences between the 2 groups when tested at 12 months (which is also when they were euthanized). Note that mice are short lived and after 6 months they are considered "mature adults".

The researchgers now plan to test varying daily doses of EVOO on humans soon - this way they can see what the minimal dosage is for beneficial effects (if any), and if there is a maximal dosage where there are negative health effects. In the meantime, enjoy olive oil in your diet - looks like it will benefit your health in a number of ways (here, here, and here). From Medscape:

Olive Oil Key Ingredient in Alzheimer's Prevention?

Extra-virgin olive oil (EVOO) appears to protect memory and learning ability and reduces the formation of beta amyloid (Aβ) plaques and neurofibrillary tangles in the brain — the classic hallmarks of Alzheimer's disease (AD) — new animal research shows. The study, conducted by investigators at Temple University in Philadelphia, Pennsylvania, suggests that it is the olive oil component of the Mediterranean diet that likely promotes healthy brain aging.... "And results are important enough to absolutely encourage people to consume greater amounts of EVOO. Given that it's been consumed for at least 2000 years, I do not anticipate any side effects," he added.  ...continue reading "Is Olive Oil Good For The Aging Brain?"

Published on Leave a comment on Lose Weight If You Can’t Smell Your Food?

The following is a study with weird results, really weird results. And it makes me think of all the times I've heard people joke: "just smelling food makes me gain weight", because we all knew it wasn't true. But what if it was true? .... The results of this study done in mice are that actually smelling the food one eats results in weight gain, and not being able to smell the food results in weight loss - even if both groups eat the same amount of food. And the "supersmellers" (those with a "boosted" sense of smell) gained the most weight of all.

What? How could that be? Yes, the study was done in mice, but perhaps it also applies to humans (the researchers think so). The researchers think  that the odor of what we eat may play an important role in how the body deals with calories - if you can't smell your food, you may burn it rather than store it. In other words, a link between smell and metabolism. Excerpts from Science Daily:

Smelling your food makes you fat

Our sense of smell is key to the enjoyment of food, so it may be no surprise that in experiments at the University of California, Berkeley, obese mice who lost their sense of smell also lost weight. What's weird, however, is that these slimmed-down but smell-deficient mice ate the same amount of fatty food as mice that retained their sense of smell and ballooned to twice their normal weight. In addition, mice with a boosted sense of smell—super-smellers—got even fatter on a high-fat diet than did mice with normal smell.  ...continue reading "Lose Weight If You Can’t Smell Your Food?"

Published on Leave a comment on Did You Have Some Chocolate Today?

Image result for dark chocolate Chocolate lovers can rejoice - because another study, which was actually a review of other studies - found that frequent consumption of chocolate, cocoa, and cocoa flavanols (an ingredient of cocoa) is linked with beneficial health effects. These included cardiovascular benefits, and dose-dependent improvements in cognition, attention, and memory. In other words - the more frequently one eats chocolate and cocoa (especially dark chocolate), the more beneficial health effects. So eat and enjoy! From Medical Xpress:

Cocoa and chocolate are not just treats—they are good for your cognition

A balanced diet is chocolate in both hands - a phrase commonly used to justify one's chocolate snacking behavior. A phrase now shown to actually harbor some truth, as the cocoa bean is a rich source of flavanols: a class of natural compounds that has neuroprotective effects. In their recent review published in Frontiers in Nutrition, Italian researchers examined the available literature for the effects of acute and chronic administration of cocoa flavanols on different cognitive domains. In other words: what happens to your brain up to a few hours after you eat cocoa flavanols, and what happens when you sustain such a cocoa flavanol enriched diet for a prolonged period of time?

Although randomized controlled trials investigating the acute effect of cocoa flavanols are sparse, most of them point towards a beneficial effect on cognitive performance. Participants showed, among others, enhancements in working memory performance and improved visual information processing after having had cocoa flavanols. And for women, eating cocoa after a night of total sleep deprivation actually counteracted the cognitive impairment (i.e. less accuracy in performing tasks) that such a night brings about. Promising results for people that suffer from chronic sleep deprivation or work shifts.

The effects of relatively long-term ingestion of cocoa flavanols (ranging from 5 days up to 3 months) has generally been investigated in elderly individuals. It turns out that for them cognitive performance was improved by a daily intake of cocoa flavanols. Factors such as attention, processing speed, working memory, and verbal fluency were greatly affected. These effects were, however, most pronounced in older adults with a starting memory decline or other mild cognitive impairments.

And this was exactly the most unexpected and promising result according to authors Valentina Socci and Michele Ferrara from the University of L'Aquila in Italy. "This result suggests the potential of cocoa flavanols to protect cognition in vulnerable populations over time by improving cognitive performance. If you look at the underlying mechanism, the cocoa flavanols have beneficial effects for cardiovascular health and can increase cerebral blood volume in the dentate gyrus of the hippocampus. This structure is particularly affected by aging and therefore the potential source of age-related memory decline in humans."

So should cocoa become a dietary supplement to improve our cognition? "Regular intake of cocoa and chocolate could indeed provide beneficial effects on cognitive functioning over time. There are, however, potential side effects of eating cocoa and chocolate. Those are generally linked to the caloric value of chocolate, some inherent chemical compounds of the cocoa plant such as caffeine and theobromine, and a variety of additives we add to chocolate such as sugar or milk." Nonetheless, the scientists are the first to put their results into practice: "Dark chocolate is a rich source of flavanols. So we always eat some dark chocolate. Every day." [Original study.]

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Published on 1 Comment on Is Coffee From Lightly Roasted Coffee Beans Best For Health?

Should the results of this study determine what kind of coffee one drinks? Does it really make a difference? Eh...Not for me (because all coffee seems to be beneficial), but it might for you.

Studies show that daily drinking of coffee appears to have health benefits. Studies have linked coffee consumption with lower rates of cancer (here and here), cardiovascular disease, and diabetes. Coffee contains beneficial chemicals (such as caffeine and chlorogenic acid) that are antioxidant and anti-inflammatory, and could help fight chronic inflammatory diseases. It turns out that how much coffee beans are roasted changes how much chlorogenic acid they contain, but the amount of caffeine basically stays the same among the different roasting levels.

Researchers in Korea compared the caffeine and chlorogenic acid components of Arabica coffee beans at different roasting levels: Light, Medium, City, and French roast. They then tested various protective antioxidant and anti-inflammatory properties of the different coffee extracts in various "cell models" (meaning in the lab, not on real people). They found that chlorogenic acid levels were higher in light roasted coffee extract than the other roasted groups, and also light roasted coffee extract had the highest antioxidant activity. The results found that increasing degrees of roasting reduced antioxidant and anti-inflammatory activities.

From the Journal of Medicinal Food: Cellular Antioxidant and Anti-Inflammatory Effects of Coffee Extracts with Different Roasting Levels

During roasting, major changes occur in the composition and physiological effects of coffee beans. In this study, in vitro antioxidant effects and anti-inflammatory effects of Coffea arabica green coffee extracts were investigated at different roasting levels corresponding to Light, Medium, City, and French roast. Total caffeine did not show huge difference according to roasting level, but total chlorogenic acid contents were higher in light roasted coffee extract than other roasted groups. In addition, light roasted coffee extract had the highest antioxidant activity.... The expression of mRNA for tumor necrosis factor-alpha and interleukin-6 was decreased in cells treated with the coffee extracts and the expression decreased with increasing roasting levels. These data suggest that coffee has physiological antioxidant and anti-inflammatory activities and these effects are negatively correlated with roasting levels in the cell models.

Coffee is one of the most popular beverages worldwide. Increasing consumption of coffee is related to the pleasing taste and aroma, as well as its physiological effects. Coffee is proposed to exert beneficial effects against cancer, cardiovascular disease, obesity, and diabetes. Coffee contains phenolic compounds such as caffeic acid, chlorogenic acid, ferulic acid, vanillic acid, and other phytochemicals. The quality of coffee is significantly related to the roasting process.... During roasting, there are numerous changes in coffee bean compound profiles and the aroma is increased. Major changes in coffee bean composition occur during roasting as a result of the Maillard reaction..... Roasting markedly affects chlorogenic acid, leading to hydrolysis of chlorogenic acid. New compounds are formed during the roasting process; one of these is melanoidin. Its formation might alter the overall antioxidant capacity of coffee beans after roasting.

Coffee is a rich source of antioxidants that may contribute to prevention of oxidative stress-related diseases. The antioxidant properties of coffee may reflect the presence of both phenolic and nonphenolic bioactive compounds, such as caffeine and chlorogenic acids. Previous studies have shown that coffee has protective effects against oxidation and DNA damage in human cell models and has been shown to possess an in vitro antioxidant activity that lessens lipid peroxidation and neoplastic activity. 

Caffeine is the major component in coffee extract and has antioxidant property. Chlorogenic acid is another well-known efficient antioxidant in coffee extract; it was highest in Light roast coffee extract and highest with low roasting temperature and lowest in Dark roasted extract. Carbohydrates, protein, and chlorogenic acid are all decreased in coffee during the roasting process.... Caffeine contents showed no differences among roasting levels, but chlorogenic acid content decreased as roasting degree increased..... The effect of coffee roasting on the antioxidant properties of coffee extracts was investigated in several earlier studies; antioxidant capacity decreased in Dark roast coffee. The antioxidant property of coffee extracts prepared with different roasting levels was also determined in this study. The best antioxidant activity was evident in Light roast coffee extract and the lowest in French roast coffee.

Published on Leave a comment on Improve Knee Arthritis Pain With A High Fiber Diet?

Another study finding health benefits of a fiber rich diet, which means lots of fruits, vegetables, whole grains, legumes (beans), nuts, and seeds. This time, researchers doing an a analysis of 2 studies lasting over a number of years found that there was an association with more fiber in the diet and less risk of developing knee osteoarthritis pain and of knee osteoarthritis symptoms worsening. The highest fiber group reported eating a median (middle number) 25.5 grams of fiber per day, while the lowest fiber group had a median of about 9 grams of fiber per day. They found a dose dependent relationship - the more fiber, the less osteoarthritis knee pain, and vice versa (the less daily fiber, the more they reported knee pain worsening) - this is called a "dose-dependent inverse relationship". The average fiber intake for Americans is about 15 grams per day.

The researchers also found that the more fiber in the diet, the lower their Body Mass Index (less weight) - but they say they took that into account in the analyses, and found that the amount of fiber intake was the most important thing regarding knee osteoarthritis pain. Interestingly, they did not find an association of fiber intake and x-ray evidence of osteoarthritis.  Note that this was an observational study - it observed that certain things go hand in hand, but it doesn't prove causation.

Osteoarthritis (OA) is common among adults aged 60 years and older, and is sometimes called "wear and tear" arthritis because it affects the joints. It causes pain and limits a person's physical functioning. There is a strong association between obesity, inflammation, and knee osteoarthritis. Obesity causes both inflammation and puts extra weight on the knees, and inflammation results in more joint pain. On the other hand, a high fiber diet reduces inflammation. The researchers point out that the data shows "a consistent protective association" between fiber in the diet and symptoms of knee osteoarthritis (no matter if you're overweight or not). IN SUMMARY: Eat lots of fruits, vegetables, legumes, whole grains, and nuts! From Science Daily:

Fiber-rich diet linked to lowered risk of painful knee osteoarthritis

A fibre-rich diet is linked to a lowered risk of painful knee osteoarthritis, finds the first study of its kind, published online in the Annals of the Rheumatic Diseases. The findings, which draw on two different long term studies, are broadly in line with the other reported health benefits of a fibre-rich diet. These include reductions in blood pressure, weight, and systemic inflammation, and improved blood glucose control.

The researchers mined data from two US studies in a bid to find out if dietary fibre might have any bearing on the risks of x-ray evidence of knee osteoarthritis, symptomatic knee osteoarthritis (x-ray evidence and symptoms, such as pain and stiffness), and worsening knee pain. The first of these studies was the Osteoarthritis Initiative (OAI). This has been tracking the health of nearly 5000 US men and women with, or at risk of, osteoarthritis since 2004-6 (average age 61), to pinpoint potential risk factors for the condition.  The second was part of the Framingham Offspring cohort study, which has been tracking the health of more than 1200 adult children of the original Framingham Heart Study and their partners since 1971.

Analysis of the data showed that eating more fibre was associated with a lower risk of painful knee osteoarthritis. Compared with the lowest intake (bottom 25 per cent of participants), the highest intake (top 25 per cent) was associated with a 30 per cent lower risk in the OAI and a 61 per cent lower risk in the Framingham study. But it was not associated with x-ray evidence of knee osteoarthritis. Additionally, among the OAI participants, eating more fibre in general, and a high cereal fibre intake, were associated with a significantly lower risk of worsening knee pain.

This is an observational study, so no firm conclusions can be drawn about cause and effect. Nevertheless, the researchers say: "These data demonstrate a consistent protective association between total fibre intake and symptom-related knee [osteoarthritis] in two study populations with careful adjustment for potential confounders." [Original study.]