Eating a healthy diet may help benefit both your body and your brain. Researchers analyzed data from 9,700 primary and secondary schools in California to find any potential connections between nutritional quality of school lunches and test score data. They found that using a healthy meal vendor (defined by a Healthy Eating Index score above the median score among all vendors) was associated with significantly higher test scores in students. This relationship was strongest for students from low-income households, possibly because they are more likely to eat the school lunch. However, the researchers did not find that working with a healthy lunch provider reduced percentage of overweight students.
National Bureau of Economic Research. 2017 Mar. 1-45. (Anderson ML et al.)

Many patients who respond well to a gluten free diet, but don’t test positive for celiac disease, are thought to have non-celiac gluten sensitivity. However, a closer look at this population is raising some doubts. Researchers in Spain analyzed data from 10 studies comprising 1312 adults, all of which were double blind, placebo controlled gluten challenges (meaning that neither the researchers nor the participants knew if they were getting a gluten-free diet or the gluten-containing placebo).  Only 16% of the non-celiac gluten sensitivity patients showed gluten-specific symptoms when exposed to the gluten-containing diet, and 40% of them had similar or increased symptoms when on the gluten-free control diet. The researchers conclude that these results “cast doubt on gluten as the culprit food component in most patients with presumptive [non-celiac gluten sensitivity].”  
Perspectives in Clinical Gastroenterology and Hepatology. 2017 Mar:15(3):339-348. (Molina-Infante J et al.) 

For couples trying to get pregnant, a healthy diet may help tilt the odds in their favor. To see what types of foods are associated with better male fertility and healthy sperm quality, researchers analyzed data on eating patterns and male fertility in 35 observational studies from around the world. They found that a healthy diet (e.g. a Mediterranean diet) with lots of seafood, poultry, vegetables, fruits, low fat dairy, and grains is associated with better sperm quality. They also found that in some studies, processed meat, soy foods,  potatoes, full fat dairy, coffee, alcohol, sugary drinks, and sweets were linked with poor sperm quality and male infertility.
Human Reproduction Update. 2017 Mar 10:1-19. (Salas-Huetos A et al.)

For those without a medically diagnosed gluten issue (such as celiac disease), the support for gluten-free and low-gluten diets appears to be more fad than fact. In a study of nearly 200,000 health professionals, researchers at Harvard found that eating lower amounts of gluten is related to a higher risk for type 2 diabetes. In fact, those in the top 20% of gluten intake were 13% less likely to get type 2 diabetes over the 30-year study period, even after adjusting for family history, exercise habits, weight, and calorie intake. (Note that research presented at meetings is considered preliminary until published in a peer reviewed journal.)
Presented at the American Heart Association’s Epidemiology and Prevention / Lifestyle and Cardiometabolic Health 2017 Scientific Sessions. Portland, OR. March 9, 2017. (Zhong G et al.)

Despite heavy marketing of the Paleo diet and lifestyle, very little is known about what our early human ancestors actually ate. To learn more about their diets, scientists in Australia studied the DNA of dental plaque from the teeth of Neanderthals (relatives of early humans) who went extinct about 40,000 years ago. While there was evidence of a meat-based diet (including wooly rhinoceros and sheep) in what is today Belgium, the Neanderthal diet in what is today Spain indicated a vegetarian diet, including mushrooms pine nuts, and moss.
Nature. 2017 Mar 8. [Epub ahead of print] (Weyrich LS et al.)

Magazines and news articles often jump from one “superfood” or fad diet to the next, but not all nutrition advice is backed up by substantial evidence. In this review, researchers analyzed the scientific support for various trending “heart healthy” foods and diets. Eating berries, nuts, extra virgin olive oil, leafy green vegetables, and plant-based diets are all strongly linked with better heart-health based on numerous studies. On the other hand, coconut oil, palm oil, eggs, juicing, and southern diets are linked with potential harm. Additionally, the researchers found no support that gluten-free diets are beneficial for people without gluten related disorders. The authors conclude that “Evidence-based healthy dietary patterns are high in fruits, vegetables, whole grains, legumes, and nuts in moderation, although some may include limited quantities of lean meats (including poultry and seafood), low-fat dairy products, and liquid vegetable oils.”
Journal of the American College of Cardiology. 2017 March 7;69(9):1172-87.

Researchers created models to estimate the percentage of US cardiometabolic deaths (deaths from heart disease, stroke, or type 2 diabetes), that can be attributed to specific aspects of a poor diet. After analyzing decades of eating pattern data from large, nationally representative surveys (NHANES), the researchers estimated that nearly half of all cardiometabolic deaths can be attributed to poor diet. Specifically, they found that high sodium diets, low nut & seed intake, high intake of processed meats (like sausage or bacon), low seafood omega-3 fats, low vegetable intake, low fruit intake, high intake of sugar sweetened beverages (like soda), and low intake of whole grains contributed the most to cardiometabolic deaths, at about 5.9-9.5% each. The researchers note that the importance of eating more healthy foods (like whole grains or vegetables) is very important, in addition to decreasing less healthy foods (like soda or bacon).
JAMA. 2017 Mar 7;317(9):912-924. (Micha R et al.)

Healthy diets nourish both people and the planet, and the savings can be quite impressive. Scientists in California created models to analyze how greenhouse gas emissions and healthcare costs might change if we decrease red & processed meat and refined grains in our standard US diet, and shift to eat more beans and peas, whole grains, fruits, and vegetables. The researchers found that opting for the healthier diets can reduce risk of heart disease, colorectal cancer, and type 2 diabetes by 20-40%, saving the US $77-93 billion per year in healthcare. These shifts can also lower greenhouse gas emissions by 222-826 kg CO2, which is equivalent to 6-23% of the US Climate Action Plan’s target. Climatic Change. 2017 Mar 6. [Epub] (Hallstrom E et al.)

Soy foods (like tofu, edamame, or soy milk) have a complicated relationship with breast cancer, since soy has estrogen-like properties. To see if eating isoflavones (the major estrogen-like compound in soy) relates to breast cancer outcomes, researchers analyzed the eating habits and health outcomes of more than 6,000 newly-diagnosed breast cancer patients (all women) in the US, Canada, and Australia. Scientists found that women eating the most isoflavones (the amount in at least ¼ cup soymilk per day) were less likely to die over the 9-year study period, but the results were only statistically significant in women with hormone-receptor-negative breast cancers (the breast cancers unlikely to respond to hormonal therapy).
Cancer. 2017 Mar 6. [Epub ahead of print] (Zhang FF et al.)

About ⅓ of breast cancer cases are hormone-receptor-negative, meaning that they are unlikely to respond to hormonal therapy. To see if diet relates to breast cancer risk, researchers analyzed the eating habits and health outcomes of more than 62,500 post-menopausal Dutch women for about 20 years. Those most closely following a Mediterranean diet were 40% less likely to develop estrogen-receptor-negative breast cancer, although overall breast cancer risk and the risk for other types of breast cancer were not significantly lower. Nut intake was the only food significantly associated with a lower risk of estrogen-receptor-negative breast cancer. For total and estrogen-receptor positive breast cancer, whole grain intake contributed the most to the lower risk, although not significantly.
International Journal of Cancer. 2017 Mar 5. [Epub ahead of print] (van den Brandt PA).

Tea is known for its disease-fighting antioxidants, but research has been unclear about the connection between tea and osteoporosis. Researchers analyzed 16 studies to find out more about this potential connection. They found that tea consumption could increase bone mineral density (how many minerals are in the bones), which decreases likelihood of developing osteoporosis. However, researchers found no association between tea consumption and fractures caused by osteoporosis, and indicated a need for more studies on the topic.
Nutrition Research. 2017 Feb 28;42:1-10. (Guo M et al.)

Home cooked meals are not only typically more nutritious than their restaurant counterparts, they often cost less too. In a random survey of 437 adults in Seattle, people who reported cooking at home frequently (at least 6x per week) tended to score higher on the Healthy Eating Index (a measure of diet quality) than those who eat out frequently. Additionally, those who report cooking at home often saved $57 per month on food costs compared to those who rarely cook (0-3x per week), while those who eat out often (at least 6x per week) spent $103 more per month on total food costs than those who report rarely eating out (0-3x per week).
American Journal of Preventive Medicine. 2017 Feb 27. pii: S0749-3797(17)30023-5. (Tiwari A et al.)