Healthy, higher fiber diets with whole grains can help lower the risk of colorectal cancer, so researchers wonder if overall dietary patterns, like the Mediterranean diet, might also be impactful. In an analysis of 13 studies, scientists found that most closely following a Mediterranean diet was linked with a lower frequency of new colorectal cancer cases, but there was no significant impact on the risk of death from colorectal cancer nor all-cause mortality in the study groups.
Am J Clin Nutr. 2020 Jun 1;111(6):1214-1225. doi: 10.1093/ajcn/nqaa083. (Zhong Y et al.)
To see how the Mediterranean diet relates to brain health, researchers analyzed the diets and health of 7,756 older adults. Those most closely following a Mediterranean diet had a significantly lower risk of cognitive impairment but did not have a significantly slower decline in cognitive function. However, those eating the most fish had both a significantly lower risk of cognitive impairment and a significantly slower decline in cognitive function.
Alzheimers Dement. 2020 Jun;16(6):831-842. doi: 10.1002/alz.12077. Epub 2020 Apr 13. (Keenan TD et al.)
The Mediterranean diet is well known for its anti-inflammatory properties, so it stands to reason that the Mediterranean diet may be helpful in the management of inflammatory bowel diseases. In a study of 284 Italian adults with inflammatory bowel diseases (including Crohn’s disease and ulcerative colitis) who were assigned to a Mediterranean diet for 6 months, eating a Mediterranean diet improved their quality of life, BMI, and waist circumference and reduced signs of fat in the liver, but did not significantly impact their cholesterol or liver function.
Inflamm Bowel Dis. 2020 May 22;izaa097. doi: 10.1093/ibd/izaa097. Online ahead of print. (Chicco F et al.)
Not all fats are created equal. Olive oil is a source of heart-healthy monounsaturated fats and polyphenols, while butter is a source of saturated fats. In this study, researchers followed more than 90,000 people for 24 years. Those eating more than ½ tablespoon of olive oil per day had a 14-17% lower risk of heart disease compared with people who didn’t eat olive oil. The scientists also found that replacing 5g/day of butter, margarine, mayonnaise, or dairy fat with the equivalent amount of olive oil was also linked with a 5-7% lower risk of heart disease.
J Am Coll Cardiol. 2020 Apr 21;75(15):1729-1739. doi: 10.1016/j.jacc.2020.02.036. Epub 2020 Mar 5. (Guasch-Ferré M et al.)
The Mediterranean diet is well known for helping prevent disease, and research suggests it may also be helpful for people who already have chronic diseases, such as type 2 diabetes. In this review, researchers analyzed existing studies (including randomized clinical trials as well as cohort studies) to see how the Mediterranean diet impacted patients with type 2 diabetes. They found that the Mediterranean diet can help reduce risk factors of diabetes complications, such as high blood pressure, inflammation, diseased blood vessels (angiopathy) and poor blood sugar control.
Adv Exp Med Biol. 2020 Apr 7. doi: 10.1007/5584_2020_513. (Gonçalves Tosatti JA et al.)
Diets can be difficult to stick to over extended periods of time, and the health benefits aren’t always long lasting. In this study, researchers analyzed 121 studies encompassing 21,942 people looking at the impacts of 14 popular diets (Mediterranean diet, low carb diet, low fat diet, etc.) after 6 months and 12 months. After 6 months, most of the diets resulted in a modest weight loss as well as improvements in blood pressure and LDL (“bad”) cholesterol. However, after 12 months, weight loss had diminished, and only those on a Mediterranean diet continued to see lower blood pressure.
BMJ. 2020 Apr 1;369:m696. doi: 10.1136/bmj.m696. (Ge L et al.)
A traditional Mediterranean diet includes frequent seafood and frequent but small portions of dairy foods, leaving some to wonder how a Mediterranean diet relates to markers of bone health. In this study, researchers analyzed the diets and vitamin D levels (using 25(OH)D blood levels) of 284 overweight and obese adults in Italy. Vitamin D levels in the blood are important to study, as they can indicate whether someone’s bones are strong or at risk of osteoporosis. Those most closely following a Mediterranean diet were significantly more likely to have higher vitamin D levels, as well as to have healthier BMI, waist size, insulin levels, and triglycerides (a type of fat in the blood). Seafood, which is abundant in the Mediterranean diet, is an important source of vitamin D, and the authors suggest that vitamin D may partially explain the Mediterranean diet’s protective effect on osteoporosis.
Int J Food Sci Nutr. 2020 Mar 29;1-7. doi: 10.1080/09637486.2020.1744533. Online ahead of print. (Zupo R et al.)
Lung function gradually declines with aging, but certain lifestyle changes may be able preserve lung function for a longer period of time. In a study of more than 2,000 adults ages 50+, those most closely following a Mediterranean diet had better lung function (as measured by peak expiratory flow rate) than those not following a Mediterranean diet, even after adjusting for factors like age, smoking history, and physical activity. When looking at specific foods, grains, dairy foods, and fish were all linked with better lung function.
Journal of the American College of Nutrition. 2020 Mar 23:1-6. doi: 10.1080/07315724.2020.1740114. [Epub ahead of print] (Papassotiriou I et al.)
A well-balanced diet is one of the best ways to set our bodies up for good health down the road, and transplant patients are no exception. In this study of 632 adult kidney transplant recipients, those most closely following a Mediterranean diet had a 32% lower risk of graft failure and kidney function decline, and a 26% lower risk of graft loss (graft being the term for the transplanted kidney).
Clinical Journal of the American Society for Nephrology. 2020 Feb 7;15(2):238-246. doi: 10.2215/CJN.06710619. (Gomes-Neto AW 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.)
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.)
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.)