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Diabetes-Protective Changes to Gut Bacteria after Year on Med Diet

In a small study, Spanish researchers randomly assigned 20 obese men to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for a year. After a year on their respective diets, both groups saw increases in various gut microbes that are thought to be protective against type 2 diabetes (Roseburia and Parabacteroides  distasonis for Med diet, and Prevotella and Faecalibacterium prausnitzii for low fat, high complex carb diet). The Mediterranean diet group also increased their insulin sensitivity over the year, meaning that their bodies better respond to insulin.
The Journal of Clinical Endocrinology and Metabolism. 2016 Jan;101(1):233-42. (Haro C et al.)

Med Diet Improves Blood Sugar Control & Heart Disease Risk Factors in Type 2 Diabetes

Chinese researchers analyzed data from nine different studies with 1178 type 2 diabetes patients being treated with the Mediterranean diet. Compared with those on a control diet (which ranged from their usual diet, to a low fat diet, to a high carb diet, to the American Diabetes Association Diet), those on a Mediterranean diet had improved blood sugar control (hemoglobin A1c, fasting glucose, and fasting insulin), improved BMI and weight loss, lower total cholesterol, triglycerides (a type of fat in the blood), and blood pressure, and improved higher HDL (good) cholesterol.
European Journal of Clinical Nutrition. 2015 Nov;69:1200-1208. (R Huo et al.) [published online 2014 Nov 4]

Moderate Wine Intake May Improve Cholesterol, Blood Sugar Control in Type 2 Diabetes

Researchers assigned over 200 patients with well controlled type 2 diabetes who don’t normally drink alcohol to eat a Mediterranean diet, and drink 5 oz of either red wine, white wine, or mineral water with dinner for 2 years. The red wine group significantly increased good cholesterol (HDL and apolipoprotein A), and the white wine group significantly decreased fasting blood sugar. “Slow alcohol metabolizers” (based on whether they carry the ADH1B*1 allele) benefited from both red and white wine on their blood sugar control. Both wine groups had improved sleep quality compared with the water group. The researchers concluded that a Mediterranean diet with moderate wine intake “is apparently safe and modestly decreases cardiometabolic risk” in patients with type 2 diabetes.
Annals of Internal Medicine. 2015 Oct 20:163(8):569-79. (Gepner Y et al.)

Replace Butter with Fish, Nuts, Seeds, and Lower Risk of Heart Disease by 25%

Harvard researchers followed over 120,000 adults for 24-30 years, tracking their diet and health records. The scientists found that replacing 5% of daily calories from saturated fat with polyunsaturated fats (found in fish, nuts, seeds, and safflower oil), monounsaturated fats (found in olive oil and canola oil), or whole grains is linked with a 25%, 15%, and 9% lower risk of heart disease, respectively. Additionally, they found that replacing 5% of daily calories from refined grains and added sugars with whole grains or polyunsaturated fats can also significantly reduce heart disease risk, and that replacing saturated fat with refined grains or added sugars does not lower heart disease risk. The researchers concluded, “Our findings provide epidemiological evidence of the current dietary guidelines, which recommend both “replacing saturated fatty acids with monounsaturated and polyunsaturated fatty acids” and “replacing refined grains with whole grains.”” The Mediterranean diet, which spotlights whole grains, fish, olive oil, nuts, and seeds, is the perfect eating plan to put these lessons into practice.
Journal of the American College of Cardiology. 2015 Oct;66(14):1538-48. (Li Y et al.)

Med Diet with Olive Oil May Prevent Diabetic Eye Damage

Complications from diabetes can lead to serious health problems, including vision impairment, blindness, and kidney damage. Using data from the PREDIMED study (where adults at risk for heart disease were assigned to either a low fat diet, a Mediterranean diet with olive oil, or a Mediterranean diet with nuts), researchers analyzed data from over 3,600 Spanish adults with type 2 diabetes, to see how diet affects the risk of diabetic nephropathy (kidney damage from diabetes) or diabetic retinopathy (eye damage from diabetes). Those following a Mediterranean diet with olive oil had a 43% lower risk of diabetic retinopathy compared to the low fat control group, and those following a Mediterranean diet with nuts had a non-significant 38% lower risk of diabetic retinopathy. There were no significant changes in the risk for diabetic nephropathy.
Diabetes Care. 2015 Sept 13. [Epub ahead of print] (Diaz-Lopez A et al.)

Lower Birth Defects Linked with Moms Who Eat Healthy Med Diets

Congenital heart defects (heart problems that occur before birth) affect nearly 1% of newborns in America. In a study of over 19,000 American women, researchers compared mothers of babies with congenital heart defects to mothers of babies without this condition. Scientists analyzed the mothers’ diets in the year before pregnancy using both the Mediterranean Diet Score and the Diet Quality Index for Pregnancy. Babies whose moms’ diets ranked healthy on both scores were significantly less likely to suffer from certain specific subgroups of congenital heart defects, such as tetralogy of Fallot (a defect in heart structure which causes oxygen poor blood to flow throughout the body), but not all heart defects. The relationship between diet and congenital heart defects was stronger with the Diet Quality Index for Pregnancy than with the Mediterranean Diet.
Archives of Disease in Childhood. Fetal and Neonatal Edition. 2015 August 24. pii: fetalneonatal-2014-308013. [Epub ahead of print.] (Botto LD et al.) 

Switching to Mediterranean Fat Sources May Help Inflammation

Palmitic acid (found in palm oil, shortening, butter, and red meat) is a type of saturated fat prevalent in the Western diet, while oleic acid (found in olive oil) is a type of monounsaturated fat prevalent in the Mediterranean diet. In a small study, researchers at the University of Vermont fed 16 adults either a diet high in palmitic acid or a diet high in oleic acid and low in palmitic acid to see how food choices affect the inflammatory response of various cells. All adults spent 3 weeks in each diet group, serving as their own control.  Although insulin sensitivity was not affected in this experiment, the scientists found that changing the diet to include more oleic acid and less palmitic acid was able to lower activation of certain cell signaling proteins (including TLR4 and NLRP3) that are associated with inflammation, oxidation and poor insulin signaling. These results suggest that shifting from a Western diet to a Mediterranean style diet (with greater proportions of oleic acid) may help fight inflammation.
Journal of Nutritional Biochemistry. 2015 Aug 1. pii: S0955-2863(15)00178-3. (Kien CL et al.)

Mediterranean Meals with Olive Oil Can Improve Blood Sugar Control, Cholesterol

In a small Italian study, researchers assigned 25 healthy adults to a Mediterranean meal (pasta, chicken breast, salad, bread, and an apple) prepared either with or without olive oil, then measured their cholesterol and blood sugar. After 30 days, the participants switched groups and ate the other meal, serving as their own control. The scientists found that 2 hours after eating, the meal without olive oil was associated with higher glucose and insulin levels, as well as higher “bad cholesterol” (LDL-C). In the second part of the experiment, the participants were assigned to a Mediterranean meal prepared with either olive oil or corn oil, switching groups after a 30 day washout period. Their blood sugar and cholesterol was tested after the meals as well. Two hours after eating, the meals with olive oil were associated with a lower increase in blood sugar and improved markers of blood sugar control (such as lower DPP, and higher GLP1 & GIP), as well as a smaller increase in “bad cholesterol” (LDL-C and oxidized LDL). These experiments indicate that meals with olive oil can help regulate blood sugar, and may help improve cholesterol.
Nutrition & Diabetes. 2015 July 20;5:e172. [Epub ahead of print.] (Violi F et al.)

Peanut and Nut Intake May Lower Death from Heart Disease

Nuts have long been associated with longevity, and new research in diverse populations further supports this relationship. Researchers tracked peanut and nut intake of about 206,000 people in the US (low income blacks and whites) and China for over 5 years. High nut intake was associated with a 21% lower risk of death from all causes among the US participants, and a 17% lower risk in the Chinese participants. High nut and peanut intake was also associated with a lower risk of death from heart disease, especially in ischemic heart disease (the type of heart disease caused by narrowed arteries).
JAMA Internal Medicine. 2015 May;175(5):755-66. (Luu HN, et al.)

Cheese Linked with Positive Microbiome Changes & Markers of Disease Prevention

Dairy foods are most often prized for their calcium content, but new research reveals that changes to the gut microbiome, especially from eating fermented dairy products, like cheese, might help explain the “French Paradox,” the phenomenon in which traditional cheeses are linked with low rates of heart disease. In a small study to investigate the protective effect of dairy foods, Danish scientists randomly assigned 15 healthy men to one of three diets for two weeks: a diet with lots of partly skim (1.5%) milk, a diet with lots of semi-hard cow’s cheese, or a control diet with butter, but no other dairy products. Both the milk and cheese diets had the same amount of calcium per day (1.7g). The men rotated through each diet, with a two-week washout period in between each new diet group. Compared to the control diet, both the cheese and milk diets were associated with significantly lower production of TMAO, a compound that is thought to be a marker of heart disease risk. The researchers also found that “dairy consumption, especially cheese, can beneficially modify the gut microbiota to increase SFCA levels.” SFCAs (short chain fatty acids) are compounds produced by gut bacteria that are linked with many health promoting effects, such as lower risk of diabetes, heart disease, and inflammatory diseases.  
Journal of Agricultural and Food Chemistry. 2015 Mar 18;63(10):2830-9 (Zheng H et al).

Doctors May Not Be Equipped for Diet Counseling

One of the great ironies of the healthcare system is that doctors are often untrained in the most basic of wellness practices: nutrition. In a survey of 236 physicians at a large US medical center (including cardiologists and internal medicine doctors and trainees), fewer than 14% felt adequately trained to discuss nutrition with their patients. Nearly all doctors (90%) recognized the Mediterranean Diet as protective against heart disease, but fewer than half (46%) realized that low-fat diets have not been proven to reduce heart disease risk. Additionally, many doctors had trouble identifying foods high in various nutrients, such as which fish are high in omega-3 fatty acids. These data highlight the importance of making reliable nutrition resources (specifically those relating to well researched eating patterns, such as the Mediterranean diet) available to the medical community. (Note: If you’re a healthcare professional who would like to learn more about the Mediterranean Diet, see here.)
Presentation at the American College of Cardiology’s 64th Annual Scientific Session. San Diego CA. March 15, 2015. 

Med Diet Cuts Heart Disease Risk by Nearly Half

Researchers have given us yet another reason to fill our plates with fruits, vegetables, whole grains, legumes, olive oil, and nuts! A European study followed more than 2,500 Greek adults for over a decade, tracking their medical records, lifestyle habits, and eating patterns. Those who most closely followed the Mediterranean Diet were 47% less likely to get heart disease, regardless of their smoking habits, age, family history, or other lifestyle factors. The scientists estimate that every one-point increase on the Mediterranean Diet score (a measure of how closely participants followed the Mediterranean Diet, on a scale of 1 to 55) is associated with a 3 percent drop in heart disease risk, so every little bit counts. In fact, the researchers found that the Mediterranean Diet was even more protective against heart disease than physical activity!
Presentation at the American College of Cardiology’s 64th Annual Scientific Session. San Diego CA. March 15, 2015.

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