HIGH FIBER INTAKE HELPS YOUR GUT BACTERIA FIGHT DIABETES

A new experimental study found that eating a diet high in fiber helps to support a healthy mix of bacteria in the gut. Previous studies have shown that people who consume more fiber have a lower risk of developing type 2 diabetes.  Fibers are beneficial because they slow down how quickly foods are digested thus blunting blood sugar spikes.  The current study reveals high fiber diets are also beneficial because they favor the proliferation of helpful gut bacteria. 

The human gut contains diverse populations of billions of bacteria that are essential to the proper functioning of the digestive system.  Many gut bacteria types break down carbohydrates into short-chain fatty acids.  These fatty acids help to nourish the cells that line the gut, reduce inflammation, and regulate hunger.  A shortage of these fatty acids has been associated with type 2 diabetes and other diseases.

In the current study, half the participants followed a standard low-fat, low-carb diet, while the other half ate a lot of high fiber foods, including whole grains, fruits and vegetables.  The experimental diet also included pre-biotic supplements, which encourage the growth of gut bacteria that make short-chain fatty acids. Both groups also took a drug called acarbose, which helps to control blood sugar by slowing the digestion of starches. This allows greater amounts of starch to reach the large intestine, where microbes feed upon it.

 After 12 weeks, participants on the high-fiber diet demonstrated a larger reduction in their 3-month average blood glucose levels. Also, their fasting blood glucose levels dropped quicker, and they lost significantly more weight than the control group.  15 strains of short-chain fatty acid-producing gut bacteria were identified in patients who consumed a high-fiber diet.  A fiber-rich diet ensured that those 15 strains became the dominant strains in the gut and produced high levels of the short-chain fatty acids butyrate and acetate.

What to do: The best way to feed the good bacteria in your gut is to eat plenty of foods high in fermentable fibers including inulin, fructooligosaccharides (FOS), resistant starches, pectins, and arabinoxylan. High-fiber foods, such as fruits, veggies, legumes and whole grains, encourage the production of short-chain fatty acids. Some specific standout choices include artichokes, leeks, onions, garlic, asparagus, wheat bran, whole wheat, barley, bananas, garlic, green bananas, beans, apples, pears, plums, carrots, and citrus. 

Source:

Liping Zhao, Feng Zhang, et al. Gut bacteria selectively promoted by dietary fibers alleviate type 2 diabetes. Science, 2018; 359 (6380): 1151. DOI: 10.1126/science.aao5774

Information adapted from articles available at:

https://www.medindia.net/news/healthinfocus/high-fiber-diet-may-help-treat-type-2-diabetes-177703-1.htm

https://www.sciencedaily.com/releases/2018/03/180308143047.htm

https://www.newscientist.com/article/2163228-a-high-fibre-diet-helps-treat-diabetes-by-changing-gut-bacteria/

https://www.medicalnewstoday.com/articles/321150.php

DRINKING FRUIT JUICE LEADS TO WEIGHT GAIN

A new study concludes that drinking 100 percent fruit juice leads to long-term weight gain, while consumption of fresh whole fruits results in weight loss.  This new report relied on data from more than 49,000 post-menopausal American women who were part of the Women's Health Initiative, a 5-year national health study.  During three years of follow-up, on average, participants gained a little more than 3 pounds.  After controlling for other factors known to impact weight including exercise, total daily calories consumed, education and income, the researchers found that women who frequently drank fruit juice were more likely to gain weight.  A single 6-ounce daily serving of 100-percent fruit juice every day prompted an average weight gain of about half a pound over three years.  This is comparable to the weight gain of individuals who regularly consume 6 oz. of sugary drinks such as lemonade and soda.  In contrast, they found that increasing consumption of whole fruits by one serving a day was associated with losing about a pound over three years.

Why is fruit juice associated with weight gain while fruits are associated with weight loss?  A 6-ounce serving of pure fruit juice contains between 15 -30 grams of sugar and 60-120 calories.  It takes multiple fruits to make even a small glass of juice so when we drink juice we are drinking the sugar of several fruits versus when we eat a fruit we are likely to consume the sugar in just one.  Also, juiced fruit does not contain the fiber in whole fruit.  The semi-solid fiber matrix of the whole fruit slows down how quickly the sugars from the fruit are digested.  In contrast, fruit juice is a liquid without significant fiber so it is digested quickly, spiking blood sugar and inducing extra insulin release.  Higher insulin production favors storage of nutrients as fat.  Juice also is not as satiating as whole fruits, leading juice drinkers to take in more total calories than fruit eaters.   

What to do:  Even though juice contains natural sugars, it is still high in sugar - just as high as many sodas.  So, when you are thirsty, drink water!  When you want something sweet, eat fruit.  If you are not a fan of water, try seltzer, unsweetened herbal tea (hot or iced), or squeezing a little lemon or orange into your water. 

Source:

Auerbach BJ, Littman AL, Krieger J et al.  Association of 100% fruit juice consumption and 3-year weight change among postmenopausal women in the in the Women's Health Initiative.  Preventive Medicine, 2018; 109: 8-10.  Available at: https://doi.org/10.1016/j.ypmed.2018.01.004

Adapted from articles available at: 

https://consumer.healthday.com/vitamins-and-nutrition-information-27/food-and-nutrition-news-316/one-hidden-culprit-behind-weight-gain-fruit-juice-731105.html

https://www.virginiamason.org/physician-links-fruit-juice-to-weight-gain