Fruits Reduce Inflammation and Heart Disease
For those who contend that eating fruit is somehow unhealthy – that fruit contains fructose and thus should be avoided – know this: The science does not support this conclusion. Nor does the body’s DNA.
Certainly we can all agree that fruit is one of the tastiest types of food available. Whether it is the sweetness of strawberries or grapes, or the tartness of tangerines – there is nothing like fresh fruit. Our salivary glands go nuts when we start peeling a citrus or start to bite into an apple. Why is that? Because our DNA has programmed the body to recognize the smell and the look of a delicious fruit. And this stimulates the flow of amylase and other enzymes to help break down the plant fibers and starches into digestible energy.
This flow of enzymes also help prepare the plant’s prebiotic fibers for our gut’s microorganisms. This is where the real benefit of fresh fruit comes from: They contain numerous prebiotic fibers that feed our microbiome. These include pectins and fructooligosaccharides (FOS). These and others nurture and feed our probiotics, allowing them to expand their colonies and provide many other benefits.
The reality is that humans have eaten fruit for hundreds of thousands of years. Fruit is programmed into our DNA. For good reason, because fruit makes our bodies healthy.
Let’s look at just two of the benefits of eating more fruit: lowering inflammation and reducing heart disease.
Eating fruit decreases heart disease
A 2015 study from the UK’s University of Leeds illustrates one of the major benefits of eating more fruit. Between 1991 and 1995, the researchers gave 30,458 women a 217-item food frequency questionnaire in order to establish their dietary intake of fruit. Individual fruits were queried and these were categorized according to their types and polyphenol profiles. The women were all free of heart disease at the beginning of the study.
The researchers then followed the women for an average of over 16 years, and measured their rates of heart disease, death from heart attacks or strokes over that period. Then the fruit intake of the women were compared with these heart diseases.
The research found that for every 80 grams a day of additional fruit eaten per day, heart disease incidence was reduced by between six and seven percent. This means that eating an additional apple per day will decrease ones heart disease risk by about 15 percent. (A 3-inch diameter apple is about 180 grams of edible fruit). And just two apples will decrease ones heart disease risk by nearly a third.
This statistic was arrived at using total fruit consumption – meaning any and all fruit.
But this doesn’t mean that all fruit is the same in terms of lowering heart disease risk. The researchers found that those who ate the most grapes had a 44 percent reduced incidence of heart attack or strokes during the 17 years. And those who ate the most citrus had a whopping 66 percent reduced incidence of heart disease or strokes during the period.
These two types of fruit are also consistent with the research on the various polyphenols in fruits.
Fruits reduce inflammation markers
Another 2015 study found that fruits – especially those with higher polyphenol levels – significantly decrease inflammation. Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging and The Friedman School of Nutrition Science and Policy at Tufts University, the Boston School of Medicine, and the UK’s Norwich Medical School at the University of East Anglia studied fruit flavonoid intake and inflammation-related diseases.
The researchers tested 2,375 people who were part of the Framingham Heart Study Offspring study. The researchers examined the individuals’ inflammatory biomarkers, and calculated their fruit intake using food-frequency questionnaires.
The researchers divided the diets into groups of five by the respective amounts of each type of fruit eaten. Those who ate the most fruit with higher anthocyanins all had significantly lower levels of all inflammatory markers compared to those who ate the least amount of those types of fruit. Strawberries and grapes stood out as having the greatest reduction of inflammatory biomarkers.
And those who ate the most fruits with higher flavonol levels had lower levels of inflammatory cytokines and oxidative stress levels compared to those who ate the lowest amount of these types of fruits.
Another 2015 study, this from Spain’s Reina Sofía University and Germany’s University of Hohenheim, had similar findings. Here researchers found that the Aronia berry – the chokeberry – actually inhibits pro-inflammatory cytokines. These include TNFα, IL-6 and IL-8 in human peripheral monocytes and the activation of the NF-κB.
What are anthocyanins?
Basically, anthocyanins are a type of polyphenol – the color pigments of red and blue that appear in many fruits. It is still up to debate precisely why anthocyanins are so good for us. There is research illustrating free radical scavenging increases.
But whether it is anthocyanins or a cofactor or derivative produced when we digest anthocyanin fruits that make them neutralize free radicals is still unknown. As shown above, anthocyanins also work on a more subtle basis, as they reduce inflammatory cytokines. (Cytokines are biochemicals that communicate with immune cells.)
There is some indication that this may relate to the gut’s microorganisms, as polyphenols have also been linked with a reduction in colorectal cancers.
Fruits that are high in anthocyanins include:
Blueberries, raspberries, red currants, grapes, blackberries, plums, açaí and cherries. Some of the highest levels can be found in Aronia (chokeberries) and concord grapes. Non-fruits with significantly high anthocyanin levels include purple corn, red cabbage, purple cauliflower and eggplants.
So go ahead and eat fruit – as long as they are fresh or whole. And don’t listen to the fructose-haters.
Lai HT, Threapleton DE, Day AJ, Williamson G, Cade JE, Burley VJ. Fruit intake and cardiovascular disease mortality in the UK Women’s Cohort Study. Eur J Epidemiol. 2015 Sep;30(9):1035-48. doi: 10.1007/s10654-015-0050-5.
Cassidy A, Rogers G, Peterson JJ, Dwyer JT, Lin H, Jacques PF. Higher dietary anthocyanin and flavonol intakes are associated with anti-inflammatory effects in a population of US adults. Am J Clin Nutr. 2015 Jul;102(1):172-81. doi: 10.3945/ajcn.115.108555.
Appel K, Meiser P, Millán E, Collado JA, Rose T, Gras CC, Carle R, Muñoz E. Chokeberry (Aronia melanocarpa (Michx.) Elliot) concentrate inhibits NF-κB and synergizes with selenium to inhibit the release of pro-inflammatory mediators in macrophages. Fitoterapia. 2015 Sep;105:73-82. doi: 10.1016/j.fitote.2015.06.009.
Olejnik A, Tomczyk J, Kowalska K, Grajek W. The role of natural dietary compounds in colorectal cancer chemoprevention. Postepy Hig Med Dosw. 2010 Apr 7;64:175-87.