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Healthy Diets Linked with Healthy Gut Microbiome in Patients with Intestinal Issues

The species of bacteria that live in our gut are thought to impact our health, so researchers wonder if diet might impact the gut microbiome of people burdened by intestinal disorders. In this study, researchers analyzed the gut microbiome of 4 different groups of people (including a general population, patients with Crohn’s disease, patients with ulcerative colitis, and patients with irritable bowel syndrome). They found that diets rich in bread, legumes, fish, and nuts were linked with lower levels of inflammatory markers and lower levels of potentially harmful aerobic bacteria. On the other hand, diets rich in meat, fast food, and sugar were linked with higher inflammatory markers. (Note that findings presented at meetings are considered preliminary until published in a peer-reviewed journal.)
Presentation at UEG Week Meeting. Barcelona. October 21, 2019. (Bolts L et al.)

Healthy Diet in Midlife Linked with Lower Risk of Cognitive Impairment Later in Life

Eating a healthy diet in mid-life can pay dividends in later decades. In this study, researchers analyzed the eating habits of 16,948 middle-aged adults in China, then assessed their brain function 20 years later. Those most closely following a Mediterranean diet or a Plant-Based Diet were 33% and 18% less likely to have cognitive impairment than those not following those diets. Other healthy diets, including the DASH diet and the alternative Healthy Eating Index, were also linked with significantly lower risks of cognitive impairment.
American Journal of Clinical Nutrition. 2019 Oct 1;110(4):912-920. doi: 10.1093/ajcn/nqz150. (Wu J et al.)

Whole-Food Plant-Based Diet Linked with Weight Loss, Healthier Gut Microbiome

Researchers randomly assigned 148 overweight and obese adults to a low-fat vegan diet, or to continue their usual diet for 16 weeks. Those in the vegan group lost about a pound per week, and also lost a significant amount of body fat. Additionally, the vegan group (who ate lots of legumes, fruits, vegetables, and nuts) also had higher levels of beneficial bacteriodetes in their gut. This may partially explain some of the health benefits of plant-based diets, because people with diabetes, insulin resistance, and inflammation tend to have low levels of bacteriodetes. (Note that findings presented at meetings are considered preliminary until published in a peer-reviewed journal.)
Presentation at European Association for the Study of Diabetes 2019 Annual Meeting. Barcelona, Spain. September 17, 2019.

Plant-Based Diets Linked with 23-30% Lower Risk of Type 2 Diabetes

Plant-based diets, which emphasize healthy plant foods like whole grains, legumes, vegetables, nuts, and fruits, and de-emphasize or eliminate animal foods like meat, dairy, and eggs, are gaining popularity among people with all sorts of dietary preferences. In this study, researchers analyzed the results of 9 observational studies totaling 307,099 participants to see how plant-based diets (including both vegan and vegetarian diets) relate to type 2 diabetes risk. Those most closely following plant-based diets had a 23% lower risk of developing type 2 diabetes across the study periods. When healthy plant-based foods, such as whole grains and vegetables, were included in the definition of plant-based, the relationship was even stronger, at a 30% lower risk.
JAMA Internal Medicine. 2019 Jul 22. doi: 10.1001/jamainternmed.2019.2195. [Epub ahead of print] (Qian F et al.)

Mediterranean and Vegetarian Diets Can Improve Cholesterol in People with Type 2 Diabetes

Poor cholesterol is a risk factor for heart disease, but dietary approaches can be used to keep cholesterol in check. In this review, researchers analyzed 52 randomized controlled trials (the “gold standard” of nutrition research) encompassing 5,360 people with type 2 diabetes, to determine the relationship between diet and cholesterol. They found that vegetarian diets most effectively reduced LDL (“bad”) cholesterol compared with control diets, and that the Mediterranean diet was the overall most effective diet to treat poor cholesterol, raising HDL (“good”) cholesterol and lowering triglycerides (a type of fat in the blood that is a risk factor for heart disease when elevated).
European Journal of Epidemiology. 2019 Jun 14. doi: 10.1007/s10654-019-00534-1. [Epub ahead of print] (Neuenschwander M et al.)

Meatless Meals Linked with Lower "Bad" Cholesterol

High cholesterol is a risk factor for heart disease, and it can be easily impacted by food choices. In this study, researchers randomly assigned more than 100 adults to a high saturated fat diet (with lots of butter and fatty dairy) that was meatless, chicken-based, or red meat-based, or a low saturated fat diet (with lowfat dairy) that was meatless, chicken-based, or red meat-based. In both groups, people followed each variation (meatless, chicken-based, or red meat-based) for 4 weeks each, in a random order. Regardless of the protein source, those in the higher saturated fat diet groups had significantly higher levels of total cholesterol and “bad” (LDL) cholesterol. Additionally, those in the meatless group (who got their protein from soy, eggs, legumes, nuts, and dairy) had significantly lower “bad” (LDL) cholesterol than those in the chicken or red meat groups, with no significant differences observed between chicken and red meat on cholesterol.
American Journal of Clinical Nutrition. 2019 Jun 4. pii: nqz035. doi: 10.1093/ajcn/nqz035. [Epub ahead of print] (Bergeron N et al.)

Plant-Based Diet Linked with Higher Antioxidant Levels, Healthier Fat Distribution

Biomarkers in blood, urine, and fat tissue can provide valuable insight into a person’s diet. In this study, researchers took samples of blood, urine, and fat tissue of more than 800 volunteers. They analyzed the participants diets and divided them into 5 categories: vegan, lacto-ovo-vegetarian, pescatarian, semi-vegetarian, and non-vegetarian. Researcher found that vegans had a significantly higher concentration of antioxidants than non-vegetarians. The results were similar, but less significant, for the other vegetarian groups. They also found that vegans and vegetarians had less saturated fat and more omega-3 fats in their blood than non-vegetarians. The healthier fat distribution and higher concentration of antioxidants and other biomarkers in the vegetarian and vegan groups may help explain some of the benefits of plant-based diets.
The Journal of Nutrition. 2019 Apr 1;149(4):667-675. doi: 10.1093/jn/nxy292. (Miles FL, et al.)

Small Amounts of Red and Processed Meat Linked with Cardiovascular Death

Seventh-Day Adventism is a religion which promotes a vegetarian diet and overall healthy lifestyle as a spiritual practice. In this study, researchers followed a cohort of over 90,000 Seventh-Day Adventists for an average of about 12 years and analyzed their consumption of red and processed meats. They found that participants who ate the most red and processed meat tended to be less physically active, were more likely to smoke tobacco and drink alcohol, and had a lower intake of fruits, vegetables, legumes, and whole grains than the participants who ate no meat at all. Compared to vegetarians, participants who ate red and processed meat were more likely to die of any cause and of cardiovascular disease. Notably, the participants who ate the most red and processed meat in this study (about 1.5 ounces per day) still have a relatively low consumption when compared to the average American diet (sometimes closer to 5 ounces per day). This suggests that even a low consumption of red and processed meats may have negative health effects.
Nutrients.  2019 Mar 14;11(3). pii: E622. doi: 10.3390/nu11030622. (Alshahrani SM et al)

EAT-Lancet Commission Outlines a Healthy, Sustainable Diet

Diet is intimately linked both to human and environmental health. In this article, a commission of distinguished scientists from different fields set out to examine the components of a healthy diet and the link between diet and environmental health. Through an extensive review of literature, the researchers found that an ideal diet that meets basic nutritional needs and can be sustainably produced is mostly plant-based. Specifically, this diet is based around about 11 ounces vegetables, 9 ounces of dairy foods (a little over a cup of milk) 8 ounces of whole grains (about 8 servings, such as a slice of bread or a ½ cup cooked grains), 7 ounces of fruit, 3 ounces of legumes, 2 ounces of nuts, and an optional 2 ounces of other animal foods (like eggs, poultry, or meat) per day. The authors suggest that a global shift towards these dietary principles can prevent approximately 11 million deaths per year, and can sustainably produce enough food for the growing population without further damage to the environment.
Lancet.  2019 Feb 2;393(10170):447-492. doi: 10.1016/S0140-6736(18)31788-4. (Willett W et al)

Plant-Based Korean Diet with Brown Rice Can Improve Blood Pressure and Blood Sugar in Hospitalized Patients

Many people are surprised at how effective lifestyle changes can be when it comes to managing chronic disease. In this study, 160 hospital patients in South Korea with high blood pressure changed their diet to eat a plant-based (vegan) diet based on brown rice at each meal, with lots of kimchi and pickled vegetables, fermented soy foods, and lots of other vegetables (both raw and cooked). They averaged about 1,700 calories per day and did not eat any refined grains or any noodles or breads, relying on brown rice as the staple. Their sodium intake was quite high, at 7,382mg per day. However, after about 2 weeks, 86% of the patients were able to stop taking their blood pressure and diabetes medications, and their reduced blood pressure levels remained stable even after stopping the medications. Similarly, HBA1C reduced from 7.6 to 7.2, indicating better blood sugar management. More research is needed to see if similar approaches might be effective in other populations.
Journal of Ethnic Foods. 2018 Nov 1. DOI: https://doi.org/10.1016/j.jef.2018.09.002 (Jung SJ et al.)

Shifting to Healthy Vegetarian Diets Could Lower Earth's Water Footprint by 35-55%

Scientists are beginning to discover that eating choices that are best for people also happen to be best for the planet. Researchers from the European Commission’s Directorate for Sustainable Resources analyzed national food surveys, water footprint databases, and other datasets across the UK, France, and Germany to determine how the water footprint changes when people shift their diet. They found that shifting from the current eating pattern to a healthy eating pattern (that contains meat) cut reduce the water footprint by 11-35%, and that even larger reductions could be made by shifting to a healthy pescatarian (vegetarian with fish) diet (33-35% reduction) or a healthy vegetarian diet (35-55% reduction).
Nature Sustainability. 2018 Sept 1. doi: 10.1038/s41893-018-0133-x. (Vanham D et al.)

Healthy Diets (Like Mediterranean, Vegetarian) May Improve Gut Microbiome

Scientists are increasingly interested in researching the gut microbiome, the community of bacteria of our digestive tract, as studies suggest that the types of microbes we produce and carry around may impact our risk for chronic disease. In this review, researchers analyzed the existing research on diet and the gut microbiome, focusing on vegetarian diets and Mediterranean diets. Both epidemiological studies and randomized clinical trials demonstrate that healthy Mediterranean and vegetarian diets are linked with various beneficial changes to the gut microbiome (such as increased short chain fatty acid production, increases in Prevotella, and decreases in trimethylamine). They suggest that these healthy diets may lower risk of chronic disease by impacting our gut microbiome, but that more research is needed to identify the exact mechanism.
Journal of Nutrition. 2018 Sep 1;148(9):1402-1407. doi: 10.1093/jn/nxy141. (Tindall AM et al.)

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