Don’t let a poor diet keep you up at night. In this study, researchers analyzed the diets and insomnia rates of more than 50,000 post-menopausal women. Eating more whole grains, fiber, fruit, and vegetables was linked with lower odds of insomnia. On the other hand, eating more added sugar, starch, refined grains, and a high glycemic index diet (diet of foods that raise your blood sugar quickly) was linked with higher odds of insomnia.
American Journal of Clinical Nutrition. 2020 Feb 1;111(2):429-439. doi: 10.1093/ajcn/nqz275. (Gangwisch JE et al.)

Healthy menu items are seemingly easier to find at restaurants than they were ten years ago, but are people actually eating these dishes? To find out, researchers analyzed the nutritional content of fast-food and full-service restaurant dishes eaten by 35,015 adults between 2003 and 2016. Although the overall diet quality remained poor for both fast-food and full-service restaurant meals eaten by the participants, there are a few promising signs of progress. Notably, whole grains eaten at restaurants increased from 0.22 to 0.49 servings per day in full-service restaurants, and 0.08 to 0.31 servings in fast food restaurants. There were also slight increases in nut/seed/legume intake at fast food restaurants, as well as slight decreases in soda consumption at full-service restaurants and saturated fat and sodium consumption at fast food restaurants. Unfortunately, over this time period, people also at fewer fruits and vegetables at both types of restaurants, and the nutritional disparities between different racial and ethnic demographic groups persisted and, in some cases, worsened.
Journal of Nutrition. 2020 Jan 29. pii: nxz299. doi: 10.1093/jn/nxz299. [Epub ahead of print] (Liu J et al.)

The Mediterranean diet is well-known for its links to brain health, and new research demonstrates that these ties hold up in populations with heart disease as well. In this study, researchers analyzed the diets of 200 men (average age 57), then assessed their brain health 14 and 20 years later. Not following a Mediterranean Diet was linked with a greater decline in overall cognitive performance and visual spatial functions.
Nutritional Neuroscience. 2020 Jan 22:1-9. doi: 10.1080/1028415X.2020.1715049. (Lutski M et al.)

While some headlines focus on the supposed benefits of choosing a low-carb or a low-fat diet, the smarter dietary move is to focus on overall diet quality, and let the numbers fall where they may. In this study, researchers analyzed the food choices of 37,233 US adults, then followed them for years to see if diet impacted risk of death. Neither low-carb nor low-fat diets were linked with death. However, when differentiating between healthy and unhealthy diets, both unhealthy low-carb and low-fat diets were linked with increased mortality risk over the study period, while healthy low-carb and low-fat diets were both linked with lower risk of mortality over the study period. Therefore, it seems that the amount of fat or carbs is less important than the quality of fat or carbs.
JAMA Internal Medicine. 2020 Jan 21. doi: 10.1001/jamainternmed.2019.6980. [Epub ahead of print] (Shan Z et al.)

Olive oil is famously healthy due in part to its polyphenol content, and researchers wonder if cooking the olive oil degrades any of its nutritional properties. In this study, research tested the phenolic content of olive oil after sautéing it at medium (about 250°F) and high (about 340°F) temperatures on the stovetop over various periods of time (15-60 minutes) to replicate home cooking. They found that temperature had a much bigger impact than time, and that cooking at a medium temperature on the stovetop decreased polyphenol content by 40%, and that cooking at a high temperature on the stovetop decreased polyphenol content by 75%. Nonetheless, they found that cooked olive oil still meets the parameters of the EU’s health claim, as it still has the level of polyphenols necessary to prevent LDL oxidation. (LDL oxidation is the creation of a dangerous type of cholesterol that can clog arteries).
Antioxidants. 2020 Jan 16;9(1). pii: E77. doi: 10.3390/antiox9010077. (Lozano-Castellón J et al.)

Coconut oil is popularly characterized as a “superfood,” yet nutrition researchers question the science supporting its health benefits. In this study, scientists analyzed 16 trials comparing coconut oil to other vegetable oils. They found that eating coconut oil significantly increased “bad” LDL cholesterol by 10.47mg/dL, and showed no benefits in terms of body fat, inflammation or blood sugar control when compared with other oils. Although coconut oil also raises “good” HDL cholesterol, the authors note that simply raising HDL is not enough to reduce the risk of heart disease. The authors also note that the medium chain “healthy fats” in coconut oil are composed of lauric acid, and therefore actually behave more like long chain fats, meaning they still contribute to raising cholesterol.
Circulation. 2020 Jan 13. doi: 10.1161/CIRCULATIONAHA.119.043052. [Epub ahead of print] (Neelakantan N et al.) 

Lifelong adherence to a gluten-free diet is a medical necessity for people with celiac disease. However, extra care must be taken to ensure that a gluten-free diet is nutritionally balanced. In this study, researchers analyzed the diets of 120 children with celiac disease who had been eating a gluten-free diet for at least 2 years, along with 100 age-and-gender-matched healthy children who didn’t avoid gluten. Those on a gluten-free diet ate significantly more saturated fat (contributing to 12.8% vs 8.8% of total calories) and significantly less fiber (12.6 g vs 15 g) daily than those not on a gluten-free diet.
Nutrients. 2020 Jan 4;12(1). pii: E143. doi: 10.3390/nu12010143.(Lionetti E et al.)

Crohn’s disease and ulcerative colitis are both types of inflammatory bowel diseases that cause serious digestive discomfort in people. In this study, scientists followed two large cohorts of people (83,147 total) aged 45-79 years old, assessed their diet, then monitored them for 17 years to see if they developed Crohn’s disease or ulcerative colitis. Those most following a Mediterranean diet were up to 58% less likely to get Crohn’s disease over the study period, but the results were not statistically significant for ulcerative colitis.
Gut. 2020 Jan 3. pii: gutjnl-2019-319505. doi: 10.1136/gutjnl-2019-319505. (Khalili H et al.)

Food choices can impact not only the nutrients we take in, but also our overall quality of life. In this study, researchers analyzed the diets of 258 adults with type 1 diabetes and surveyed them about their quality of life. Those closely or even moderately following a Mediterranean diet were more likely to have a better diabetes-specific quality of life than those not following a Mediterranean diet. Following a more general healthy diet (as measured by the alternate Healthy Eating Index) had mixed results on quality of life, scoring highly in some categories, but low in others.
Nutrients. 2020 Jan 2;12(1). pii: E131. doi: 10.3390/nu12010131. (Granado-Casas M et al.)

Chili pepper is an underappreciated aspect of a Mediterranean diet. To see how it relates to longevity in a Mediterranean population, researchers analyzed the diets of 22,811 Italian adults and monitored their health outcomes for 8 years. Those eating chili pepper at least 4 times per week were 23% less likely to die from all causes and 34% less likely to die from heart disease over the study period, even after controlling for the benefits of a Mediterranean diet. The relationship seems to be strongest in people without high blood pressure.
Journal of the American College of Cardiology. 2019 Dec 24;74(25):3139-3149. doi: 10.1016/j.jacc.2019.09.068. (Bonaccio M et al.)

Chili peppers are included in many traditional diets around the world. In this study, researchers followed 22,811 Italian adults for 8 years to study the relationship between eating chili peppers and health outcomes. Those eating chili peppers at least 4 times per week had a 34% lower risk of death from heart disease, a 61% lower risk of death from stroke, and a 23% lower risk of death from all causes than those rarely or never eating chili peppers.  Although those eating more chili peppers were also more likely to follow a Mediterranean diet, the lower risk of death remained significant even after adjusting for diet quality. Chili peppers contain many healthy plant compounds with antioxidant properties (such as capsaicin, beta carotene, and flavonoids) that may contribute to the peppers’ protective effect.
Journal of the American College of Cardiology. 2019 Dec 24;74(25):3139-3149. doi: 10.1016/j.jacc.2019.09.068. (Bonaccio M et al.)

Eating a healthy, well-balanced diet is known to help prevent numerous chronic diseases, so it’s no surprise that eating healthier can reduce healthcare costs, too. In this study, researchers analyzed U.S. eating habits against dietary recommendations, and then calculated the cardiometabolic disease burden (heart diseases, stroke, type 2 diabetes) attributable to not meeting specific dietary guidelines. From there, they were able to calculate the costs associated with not meeting specific dietary recommendations. They found that diet-related healthcare costs were $301 per person annually (or $50.4 billion total) for cardiometabolic diseases alone. Specifically, the per-person annual cardiometabolic cost of not eating enough nuts & seeds was $81, seafood omega-3 fats was $76, vegetables and legumes was $60, fruits was $57, and whole grains was $45.
PLoS Medicine. 2019 Dec 17;16(12):e1002981. doi: 10.1371/journal.pmed.1002981. eCollection 2019 Dec. (Jardim TV et al.)