Archeologists analyzed the preserved plant remains at an Acheulian site in Israel to determine the role of plant foods (if any) in ancient diets. Contrary to the popular, meat-centric interpretation of a paleo diet, the researchers argue that “a wide spectrum of food plants was a permanent aspect of the pre-agricultural hominin economy,” and that the abundance of fruit, nut, seed, and grain plants “is a result of deliberate hominid behavior.” The researchers also found “ample evidence for the important role of fire at GBY [Gesher Benot Ya’aqov], with its control and repeated uses shown by burned lithics and charred wood, bark, grains, and fruits. The plant remains, dating back about 780,000 years, led researchers to conclude that “our results change previous notions of paleo diet.”
Proceedings of the National Academy of Sciences of the United States of America. 2016 Dec 20;113(51):14674-14679. (Melamed Y et al.)

The Mediterranean diet is a gold standard of healthy eating, and now scientists are learning more about the reasons behind its health benefits. Researchers randomly selected 75 adults (ages 55 to 80) with metabolic syndrome from one of three groups from the PREDIMED trial: a low-fat control diet, a Mediterranean diet with olive oil, or a Mediterranean diet with nuts. All participants had either type 2 diabetes or three or more risk factors for heart disease (smoking, high blood pressure, overweight or obesity, or family history of heart disease). Blood sample analysis revealed that both Mediterranean diet groups had better plasma antioxidant defenses and decreased xanthine oxidase activity (an enzyme linked with oxidative stress and health problems), but no difference in oxidative damage was found between the three groups. The researchers conclude that this antioxidant effect “could at least partially account for the previously reported beneficial effects of [the Mediterranean diet].”
Molecular Nutrition & Food Research. 2016 Dec;60(12):2654-2664. (A Sureda et al.)

Nuts are an important source of healthy fats and protein in traditional diets. After analyzing 20 prospective cohort studies, researchers found that those eating the most nuts (peanuts and tree nuts total) had a 24%, 11%, 19%, 18%, and 19% lower risk of coronary heart disease, stroke, cardiovascular disease, total cancer, and all-cause mortality, respectively. The scientists estimate that even eating just one 15-20g serving of nuts each day (about 2-3 tablespoons) is associated with a protective effect.
BMC Medicine. 2016 Dec;14(1):207. (D Aune et al.) 

Scandinavia has 2 to 3 times the rate of hip fracture compared to Southern Europe. To assess the role of diet in this geographic discrepancy, researchers analyzed two large Swedish cohorts totaling 71,333 people (average age 60) over 15 years, to determine the rate of hip fracture in people with different adherence levels to the Mediterranean diet. Most closely following a Mediterranean diet was associated with 22% lower hip fracture rate, and a 1 year higher age at hip fracture, compared to not following a Mediterranean diet.
Journal of Bone & Mineral Research. 2016 Dec;31(12):2098-2105. (L Byberg et al.)

Genetics play a large role in disease prevention, but your genes are not your destiny. To determine how healthy lifestyles might mitigate the risk of heart disease, researchers analyzed the genetic risk factors and lifestyle patterns of more than 31,000 men and women across 3 cohorts. The researchers defined a healthy lifestyle by following at least 3 of the following criteria: not being obese, not smoking, exercising at least once per week, and eating a healthy diet. (Those with an unhealthy lifestyle followed 1 or fewer of the criteria). The scientists found that while both genetic and lifestyle factors were independently associated with heart disease risk, having a healthy lifestyle was associated with a 46% lower risk of heart disease in people who are genetically predisposed to heart disease.  
New England Journal of Medicine. 2016 Dec 15;375(24):2349-2358. (Khera AV et al.)

Food may be known to influence our mood, but little is known about the relationship between food choices and mental health. In an Australian study, scientists evaluated the Glycemic Index (a measure of how quickly carbohydrates spike blood sugar) and carbohydrate choices of 1,918 adults’ diets. Participants whose eating habits were highest on the Glycemic Index had a 55% higher likelihood of having depressive symptoms, compared to those with the lowest Glycemic Index intakes. When analyzed by the source of fiber, diets higher in total fiber (more than 27 grams per day), and fiber from vegetables and breads/cereals (mostly whole grain) were associated with a 42%, 46%, and 41% reduced likelihood of having depressive symptoms, respectively. Vegetable consumption was also linked with a significantly lower risk of depressive symptoms.
British Journal of Nutrition. 2016 Dec;116(12):2109-2114. (Gopinath B et al.)

Good dental hygiene is essential for healthy gums, but the foods we eat might help protect us against gum disease as well. To see how eating patterns relate to gum health. researchers analyzed national survey data from 6052 US adults. They found that people eating at least 1.5 servings of whole grains per day were significantly less likely to have severe gum disease than those not eating whole grains. Similarly, those eating fewer than 12 grams fiber per day were 27% more likely to have increasing severity of gum disease. However, fruit and vegetable intake was not significantly related to gum health.
The Journal of Nutrition. 2016 Dec;146(12):2530-2536. (Nielsen SJ et al.)   

More and more professional athletes are embracing plant-based diets, and for a good reason.  To see how diet relates to athletic abilities scientists analyzed the strength and oxygen uptake of 27 vegetarian athletes and 43 omnivorous athletes. They found that while there was no significant difference in strength (measured by torque) between vegetarian and non-vegetarian athletes, female vegetarian athletes had better oxygen uptake (measure by VO2 max) than their non-vegetarian counterparts (no significant difference for males). The authors conclude that “following a vegetarian diet may adequately support strength and cardiorespiratory fitness development, and may even be advantageous for supporting cardiorespiratory fitness.”
Nutrients. 2016 Nov 15;8(11). pii: E726. (Lynch HM et al.) 

Fat is essential to the diet, but certain fats are better than others. Scientists analyzed the eating patterns and health outcomes of more than 115,000 men and women in the Nurse’s Health Study and the Health Professionals Follow Up Study. The scientists found that those eating the most saturated fats (the types of fats found in red meat, butter, and milk) were more likely to get heart disease over the 24-28 year study period. In fact, replacing just 1% of calories from saturated fat with the same amount of calories from whole grains, polyunsaturated fats (found in fish, nuts, and seeds), or plant proteins (such as beans or nuts) is linked with a 6-8% lower risk of heart disease. The scientists conclude that “dietary recommendations for the prevention of coronary heart disease should continue to focus on replacing total saturated fat with more healthy sources of energy.”
British Medical Journal. 2016 Nov; 355:i5796. (G Zong et al.)

A Mediterranean lifestyle encompasses much more than just red wine and olive oil; physical movement and social connection are also important as well. To this point, researchers followed 11,800 Spanish adults for 8.5 years monitoring their eating patterns, lifestyle, and health outcomes. Those most closely following a Mediterranean Diet were 18% less likely to develop depression over the 8.5-year study. Similarly, those with the most physical activity and social activity were 19% and 23% less likely to develop depression, respectively. However, a Mediterranean lifestyle, which encompasses diet, physical activity, and social activity, seemed to be most effective, as it was linked with a 50% lower risk of depression. 
Clinical Psychological Science. 2016 Nov. 4(6):1085-10093. (Sanchez-Villegas A et al.)

Plant-based diets are shown to be more sustainable, but nutrition researchers want to know if they are as satiating as meat-centric meals. In a randomized, double-blind study, 43 healthy young men were given a patty made from either veal and pork (high protein), fava beans and split peas (high protein), or fava beans and potatoes (low protein). The participants rotated through each of the 3 meals (with a 2-week washout in between each one), serving as their own controls. Although the fava and split pea patty was rated as less palatable than the other two meals, it proved to be the most satiating, with participants reporting less hunger and appetite afterwards, and participants didn’t need to eat as much at the following meal to feel full. While both the fava/pea patty and veal/pork patty were both high protein, the additional fiber in the fava/pea patty could also have contributed to the fullness.
Food and Nutrition Research. 2016 Oct 19;60:32634. (Kristensen MD et al.)

In a small study, researchers assigned overweight and obese adults in Ohio to one of two diets for 8 weeks, one with whole grains, one with refined grains. After going back to their normal diet for 10 weeks as a washout, the 33 participants then switched diets, serving as their own control. Both diet groups lost weight and body fat, and lowered their systolic blood pressure (the top number in a blood pressure reading), total cholesterol, and LDL (“bad”) cholesterol. The scientists also found that the whole grain diet reduced diastolic blood pressure (the bottom number in the blood pressure reading) by 5.8 mm Hg, “or an additional 4.2 mm Hg beyond any change attributable to weight loss.” According to the researchers, this improvement, which was 3-fold greater in the whole grain group than the refined grain group, “approximates to a 40% lower risk of dying from stroke and a 30% lower risk of dying from ischemic heart disease or other vascular causes.”  
The Journal of Nutrition. 2016 Oct 19. pii: jn230508. [Epub ahead of print] (Kirwan JP et al.)