The gut microbiome is a fascinating new area of research, with implications in the prevention of many chronic diseases. To see how diet might play a role, researchers at the University of Alberta in Canada analyzed data on microbiome depletion. They found that dietary fiber is “the only factor that has been empirically shown to be important” to a healthy, diverse microbiome, but that unfortunately, most people do not eat enough fiber to meet the daily recommendation (which is 25-38g per day for most adults in the US). Fiber rich foods include many whole grains, vegetables, fruits, pulses, nuts, and seeds.
Trends in Endocrinology & Metabolism. 2016 May;27(5):239-42. (Deehan EC et al.)

Nutrition education is a valuable tool to fight increasing obesity rates among teens, especially for those at a higher risk, such as African-Americans. Researchers compared a nutrition education curriculum focusing on spices and herbs (“Spice MyPlate”) to a basic nutrition education program based on USDA MyPlate guidelines on 110 (predominantly African-American) teens in Baltimore, Maryland. Twelve spices and herbs were chosen for the core focus of the Spice MyPlate curriculum: cinnamon, black pepper, red pepper, basil, garlic, oregano, thyme, nutmeg, ginger, turmeric, rosemary, and cumin. Participants in the Spice MyPlate group reported they were more likely to eat vegetables, low-fat dairy, and lean protein after the intervention. They also reported that they would be more likely to eat vegetables and whole grains if they were flavored with spices and herbs.
American Journal of Health Promotion. 2016 May;30(5):346-356. (D’Adamo CR et al.)

To see how eating pulses (beans, peas, lentils, and chickpeas) affects weight loss, Canadian researchers reviewed data from 21 six-week or longer randomized clinical trials, spanning 940 (predominately overweight and obese) participants total. Overall, the studies found that, compared to diets without pulses, diets with one 0.5-0.75 cup serving of pulses per day resulted in a 0.74 pound (0.34 kg) weight loss, even without cutting calories. The scientists concluded that eating pulses “may be a beneficial weight-loss strategy because it leads to a modest weight-loss effect even when diets are not intended to be calorically restricted.”
The American Journal of Clinical Nutrition. 2016 May;103(5):1213-23. (Kim SJ et al.)

Studies continue to show that eating a Mediterranean−style diet during pregnancy is linked with improved health outcomes for both the mother and infant. Because some pregnant and lactating women are falling short of dietary recommendations, researchers suggest that incorporating avocados into maternal diets is an easy way for women to get significant sources of nutrients they are currently lacking. Avocados are a Mediterranean−style food, rich in folate, potassium, carotenoids, fiber, monounsaturated fatty acids (MUFA) and antioxidants, all of which pregnant, lactating, and child−bearing age women need especially, in order to reduce the risk of birth complications and defects.
Nutrients. 2016 May;8(5):doi:10.3390/nu8050313. (Comerford KB et al.)

Fruit is a central component of a healthy diet, but new research suggests that fruit intake throughout various points in the lifecycle might be especially important. To see how our teenage eating habits might impact us later in life, Harvard researchers analyzed the diets and health outcomes of more than 44,000 women. They found that women who reported eating 3 servings of fruit per day in adolescence were 25% less likely to develop breast cancer in adulthood than those who reported eating only a half serving of fruit per day.
British Medical Journal. 2016 May 11;353:i2343. (Farvid MS et al.)

Wine is certainly one of the most popular aspects of the Mediterranean diet, but many wonder if other adult beverages have a similar relationship with disease prevention. To see how different alcoholic drinks relate to type 2 diabetes, Chinese researchers reviewed data from 13 different studies covering 397,296 people. They found that although a moderate amount of beer and spirits was related to a slightly decreased risk of type 2 diabetes (4%, and 5%, respectively), wine was linked with a much more significant decreased risk of type 2 diabetes, at 15%. Furthermore, all levels of wine consumption (up to about 3oz per day – the highest average of the participants) showed a protective effect against type 2 diabetes, but higher levels of beer (more than 3 oz per day) and spirits (more than 23 grams per day – less than one ounce) were linked with a higher risk of type 2 diabetes.
Journal of Diabetes Investigation. 2016 May 10. [Epub ahead of print] (Huang J et al.)

While there is still much to learn about the gut microbiome, what we do know is that certain microbes appear to be more beneficial than others, and that a large diversity of different microbes seems to be protective. To figure out what constitutes a “normal” gut microbiome, European researchers combined microbiome data from nearly 4,000 people across the US and Western Europe. The researchers found that even within this large sample size, they have not yet uncovered the total richness of gut diversity. The scientists also analyzed a number of lifestyle and health factors to see if they might affect microbiome composition. After medication use and stool consistency, dietary factors (preference for whole grain bread, high fiber intake, and high fruit intake) were pinpointed as probable contributors of healthy gut diversity. 
Science. 2016 Apr 29;352(6285):560-4. (Falony G et al.)

Forests are an important harbor of biodiversity and carbon storage, so cutting into forests to create more cropland could be very harmful to the ecosystem. To see how we can feed a growing world without cutting into forests, Austrian researchers analyzed 500 different scenarios with varying levels of cropland expansion, dietary patterns, and crop yields.  They found that “a large range of options exist to feed a no-deforestation world,” by 2050, but greatly varied based on what types of foods we’d choose to eat. For example, their models found that if the current North American diet (lots of meat and highly processed foods) continues to expand globally, only 15% of the scenarios involving this eating pattern are feasible. However, “all vegan scenarios and 94% of the vegetarian scenarios are feasible,” indicating the overall sustainability of plant based diets.
Nature Communication. 2016 Apr 19;7:11382. (Erb KH et al.)

Women who have had gestational diabetes (diabetes during pregnancy) are at an increased risk of developing high blood pressure. To see how diet might relate to this trend, researchers monitored the eating patterns and health records of more than 3,800 women who had previously been diagnosed with gestational diabetes. After adjusting for BMI, age, and other demographic factors, the women most closely following a Mediterranean diet had a 30% lower risk of developing high blood pressure over the 18-year study. Similarly, women following other healthy eating patterns (such as the DASH diet) that emphasized fruits, vegetables, and whole grains, and were low in red and processed meats, had a 24-28% lower risk of developing high blood pressure.
Hypertension. 2016 April 18. [Epub ahead of print.] (Li S et al.)

The current recommendation for pregnant women is to eat 2 cups of fruit per day (3−4 servings). However, a recent study suggests that eating as many as 3 cups of fruit per day (6−7 servings) during pregnancy is linked with improved memory and brain function of infants. In this study, Canadian researchers looked at how eating fruit during pregnancy affects babies. In a group of more than 650 babies, the researchers found that eating more fruit during pregnancy was associated with beneficial effects on babies’ brains, regardless of the mother’s level of education, socioeconomic status, other eating habits, and daily vitamin intake.
EBioMedicine. 2016 April;EBIOM−00578;No of Pages 10. (Bolduc FV et al.)

Those looking to drop the pounds need not eliminate fat from their diet, especially if they follow a Mediterranean diet. To evaluate the Mediterranean diet’s effect on weight loss, researchers reviewed data from 5 randomized controlled trials (one of the strongest types of research studies) encompassing a total of 998 participants. In each of the studies, overweight and obese adults (most having type 2 diabetes or heart disease) were assigned to either a Mediterranean diet, or another diet (low fat, low carbohydrate, or American Diabetes Association diets) for at least a year. Those in the Mediterranean diet groups lost between 9-22 pounds, in line with the results from the low carbohydrate or the American Diabetes Association diet. However, those in the low fat group lost significantly less weight, between 6-11 pounds total. Participants with type 2 diabetes also saw better improvements in blood sugar control on the Mediterranean diet than in other diets.
American Journal of Medicine. 2016 Apr;129(4):407-415.e4. (Mancini JG et al.)

New research suggests that the old adage rings true: An apple a day may in fact keep the doctor away. In a study of more than 450,000 Chinese adults, people who ate fresh fruit daily had a 34% lower risk of heart attack, a 25-36% lower risk of stroke, and a 40% lower risk of death from heart disease than those who never or rarely ate fresh fruit (less than once per month). Additionally, the systolic blood pressure (the top number in the blood pressure reading) of the daily fresh fruit eaters was 4 mm Hg lower than that of the people who never or rarely ate fresh fruit. The researchers report that “There was a strong log-linear dose-response relationship between the incidence of each outcome and the amount of fresh fruit consumed,” meaning that the more fresh fruit someone ate, the less likely they were to have heart disease.
New England Journal of Medicine. 2016 Apr 7;374(14):1332-43. (Du H et al.)