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Mediterranean Diet May Be Linked with Improved Fertility, More Research is Needed

A Mediterranean diet includes many of the foods and food groups that are recommended for fertility, so researchers set out to measure if the Mediterranean diet itself had any relationship on fertility markers. In a systematic review and meta-analysis of 11 studies, researchers found that following a Mediterranean diet is linked with live births, pregnancy rate, sperm concentration, and sperm count, but that these outcomes are inconsistent across the studies. The researchers conclude that a Mediterranean diet “indicates sperm improvement and a possibility of better pregnancy outcomes,” but that data are insufficient to make clinical recommendations.
Nutr Rev. 2023 Jun 9;81(7):775-789. doi: 10.1093/nutrit/nuac087. (Muffone ARMC et al.)

Eating More Whole Grains Linked with Better Mental Health

Whole grain’s protective effect against heart disease and diabetes is well-documented, and because these chronic conditions also relate to risk of brain health and mental health, researchers wanted to examine this relationship directly. In this study, scientists analyzed 23 studies on whole grain intake and risk of cognitive decline, depression, anxiety, and mood disorders and evaluated the strength of the evidence. They found that people who eat more whole grains are more likely to have better mood, depression, and anxiety scores. The evidence on whole grains and cognition was inconclusive, meaning that more research is needed.
Adv Nutr. 2023 Apr 19;S2161-8313(23)00288-0. doi: 10.1016/j.advnut.2023.04.003. (Ross AB et al.)

More Than 1/4 Global Cases of Type 2 Diabetes Attributed to Low Whole Grain Intake

Type 2 diabetes is one of the most prevalent chronic diseases around the world, impacting millions of people. In this study, researchers developed risk-assessment models to estimate how much various dietary habits contribute to type 2 diabetes risk in 184 countries around the world. The largest burden (26.1%) of type 2 diabetes was attributed to low whole grain intake. Other factors contributing to high type 2 diabetes burden included high intake of refined rice and wheat (24.6%) and high intake of processed meat (20.3%).
Nat Med. 2023 Apr;29(4):982-995. doi: 10.1038/s41591-023-02278-8. Epub 2023 Apr 17. (O’Hearn M et al.)

Mediterranean Diet Linked with Lower Risk of Heart Disease, Death in At-Risk Individuals

At Mediterranean diet is well-known for its link with heart health, but researchers wanted to see how this tried-and-true eating pattern stacks up against other popular diet plans, like low carb or low sodium. In this systematic review and meta-analysis, researchers analyzed 40 studies in which a total of more than 35,000 people at risk of heart disease were randomly assigned to 7 different popular diets or a minimal intervention control group, to see which popular diets are most effective of preventing heart disease and mortality. They found that Mediterranean diets reduce the risk of all-cause mortality by 28%, heart disease mortality by 45%, stroke by 35%, and nonfatal heart attacks by 52%. Mediterranean diets were more effective than any other diet studied, many of which were no better than the control group.
BMJ. 2023 Mar 29;380:e072003. doi: 10.1136/bmj-2022-072003. (Karam G et al.)

Mediterranean Diet More Affordable and Nutritious Than Typical Western Diet

Healthy eating is assumed to be more expensive, but if you actually price it out, a well-planned Mediterranean diet can be more affordable than the typical Western diet eaten today. Researchers in Australia priced out grocery baskets for 7 days worth of meals following a Mediterranean diet, a typical Western diet, and a diet based on the Australian Guide to Healthy Eating (Australia’s dietary guidelines). The groceries were also analyzed for their ability to meet recommended nutrient intakes. Both the Australian Healthy Eating basket and the Mediterranean diet basket met nearly all nutrient needs, while the typical Western diet basket did not. The Mediterranean diet basket was found to be cheaper than the Australian Healthy Eating Basket for nearly all family sizes (except $3 more per week for single-person households) and cheaper than the typical Western diet at all family sizes studied. 
Nutrients. 2023 Mar 30;15(7):1692. doi: 10.3390/nu15071692.(Bracci EL et al.)

Mediterranean Diet Linked with 23% Lower Risk of Dementia, Regardless of Genetic Risk Factors

Mediterranean diets have been linked with brain health and lower dementia risk in small studies, but researchers wanted to see how this relationship holds up in larger studies and in people who are genetically predisposed to dementia. In a study of 60,298 older adults in the UK, those most closely following a Mediterranean diet were 23% less likely to develop dementia over the 9 year study period, independent of a person’s genetic risk for dementia.
BMC Med. 2023 Mar 14;21(1):81. doi: 10.1186/s12916-023-02772-3. (Shannon OM et al.)

Mediterranean Diet Linked with 25% Lower Risk of Coronary Heart Disease in Women

Heart disease is the number one cause of death in women, meaning that lifestyle changes to support heart health are of the utmost importance. In a meta-analysis of 16 prospective cohort studies (in which more than 700,000 women were followed over time), women most closely following a Mediterranean diet were 24% less likely to develop cardiovascular disease, were 23% less likely to die, and were 25% less likely to develop coronary heart disease than those not following a Mediterranean diet.
Heart. 2023 Mar 14;heartjnl-2022-321930. doi: 10.1136/heartjnl-2022-321930. (Pant A et al.)

Eating Whole Grains Linked with 28-36% Lower Risk of Dementia

Brain-healthy diets include a variety of healthy ingredients, and researchers wonder if whole grains specifically might be related to dementia risk. In a study of 2,958 adults in the U.S., those eating the most whole grains were 28% less likely to develop all-cause dementia and were 36% less likely to develop Alzheimer’s dementia over the 12-year study period. The researchers note that more research is needed to better understand this relationship.
J Prev Alzheimers Dis. 2023;10(1):133-136. doi: 10.14283/jpad.2022.91. (J Wang et al.)

Mediterranean Diet During Pregnancy Linked with 21% Lower Risk of Adverse Pregnancy Outcomes

Adverse pregnancy outcomes (such as preeclampsia, eclampsia, gestational hypertension, gestational diabetes, preterm birth, small-for-gestational age, and stillbirth) can put both mothers and babies at risk. In this prospective study of 7,798 pregnant women across the US, those most closely following a Mediterranean diet were 21% less likely to develop any of the adverse pregnancy outcomes described above and were also 28% less likely to develop preeclampsia and 37% less likely to develop gestational diabetes. The researchers noted a dose-response relationship for risk of adverse pregnancy outcomes, meaning that the closer a mother’s diet aligned with the Mediterranean diet, the lower the risk.
JAMA Netw Open. 2022 Dec 1;5(12):e2248165. doi: 10.1001/jamanetworkopen.2022.48165.

Mediterranean Diet Linked with Lower Risk of Frailty in Older Adults

Frailty in aging may lead to falls, fractures, disability, and other serious health risks, so dietary strategies to prevent frailty in older adults are of great importance. In a study of 2,384 nonfrail adults from the Framingham Offspring Study (average age 60 years), those most closely following a Mediterranean diet had a 38% lower risk of developing frailty than those not adhering to a Mediterranean diet. Additionally, each 10-mg increase of total carotenoids and vitamin E (antioxidants found in many Mediterranean diet foods) reduced the risk of frailty by 16%.
Am J Clin Nutr. 2022 Sep 2;116(3):630-639. doi: 10.1093/ajcn/nqac130. (Millar et al.)

Dietitians and Nutrition Students Are Knowledgeable About Whole Grains, Can Play Role in Encouraging Greater Whole Grain Intake Among Consumers

In this study, researchers surveyed 348 registered dietitians and 124 nutrition students about whole grain foods. Both groups had high whole grain knowledge and were able to correctly identify whole grain foods. The authors note that exposure to whole grain foods plays a critical role in behavior change, and that “the use of prominent and clear whole-grain labeling should be increased, such as the Whole Grain Stamp.”
Nutrition Today2022 July/Aug;57(4):200-208. (Hicks-Roof K et al.) doi: 10.1097/NT.0000000000000550

Increasing Whole Grains, Limiting Beef in School Lunches Can Reduce Environmental Impact

Meals served in the National School Lunch Program are developed with nutrition, cost, and youth preferences in mind, with little room or direction to consider environmental impact. Using data from over 2.2 million real-world lunches, researchers at Tufts quantified the environmental footprint of each lunch served to see if they could determine patterns and form recommendations for more sustainable lunches. They found that low impact school lunches had “20% more whole grains, nearly 20 times more nuts and seeds, and four times less animal protein than high impact lunches.” As a result, the authors concluded that “increasing whole grain requirements and providing serving size or frequency limits for beef” are the two most effective recommendations for reducing the environmental impacts of the National School Lunch program. 
Nature. 2022 June 23;3(138). doi: 10.1038/s43247-022-00452-3. (Stern AL et al.)