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High Fiber and Fermented Foods May Benefit Microbiome

The foods we eat can impact our gut microbiome, which in turn can impact a number of health functions, including immune response and inflammation. In a small study of people randomized to either a high-fiber diet or a high-fermented-foods diet, fermented foods were found to improve the diversity of the microbiome and decrease inflammation, while high-fiber foods were found to impact the microbiome and trigger a personalized immune response.
Cell. 2021 Aug 5;184(16):4137-4153.e14. doi: 10.1016/j.cell.2021.06.019. Epub 2021 Jul 12. (Wastyk HC et al.)

Sorghum Linked with Many Health Benefits

Sorghum is a nutritious ancient grain with a low environmental footprint. In this review, researchers analyzed 16 intervention studies about sorghum and health, and found that eating sorghum may benefit blood sugar, weight management, satiety, and oxidative stress. Sorghum’s nutritional benefits and culinary versatility suggest that this grain may be an important part of future food innovations.
Critical Reviews in Food Science and Nutrition. 2021 Jul 30;1-19. doi:10.1080/10408398.2021.1944976. Online ahead of print. (Ducksbury C et al.)

Traditional Plant-Based Foods are Healthier than Novel Meat Replacements

Today there are a growing number of innovative meat-replacement products available for people seeking plant-based alternatives. But are these options necessarily healthier than traditional plant-based foods like legumes and vegetables? To find out, researchers modeled a typical omnivore (meat-containing) diet and then compared it to diets that substituted either traditional or novel plant-based foods in place of meat matched for calories and macronutrients (carbohydrates, fat, protein). Nearly all diets with traditional plant-based foods met nutrient requirements for calcium, potassium, magnesium, zinc, and vitamin B12, while the diets with the novel meat-replacements did not. Additionally, diets with the traditional plant-based foods had less saturated fat, sodium, and sugar than the meat-containing diet, while the diets with the novel meat-replacement products had more.
Nutrients. 2021 Jul 23;13(8):2527. doi: 10.3390/nu13082527. (Tso R et al.)

Whole Grains Linked with Better Maintenance of Waist Size, Blood Pressure, Blood Sugar

Larger waist sizes (as measured by waist circumference), high blood pressure, and high triglycerides are all signs of potential heart disease down the road, so researchers wonder how whole grains might play a role in these risk factors. In a study of 3,121 adults (average age 55), researchers analyzed the types of grain foods they ate and their health markers to see how different types of grains might relate to cardiometabolic risk. While all study participants got larger around the waist over the 18-year study period, eating the most whole grains (at least 48 grams whole grain per day, or at least 3 full servings) was linked with significantly smaller increases in waist size compared with eating the least whole grains (less than 8 grams whole grain per day, or less than a half serving). Additionally, eating more whole grains was also linked with significantly smaller increases in fasting blood sugar and systolic blood pressure, while eating more refined grains (4+ servings per day) was linked with greater increases in waist size and a smaller decline in triglycerides (a type of fat in the blood).
Journal of Nutrition. 2021 Jul 13;nxab177. doi: 10.1093/jn/nxab177. (Sawicki CM et al.)

Whole Grain Intake in Latin America Falls Short of Recommendations

Dietary guidelines around the world recommend making more of our grains whole, and researchers wonder if people in different countries are meeting these goals. In a study of 9,128 people across eight Latin American countries, the average person was eating less than one full serving (only 14.7 grams) of whole grain foods per day. Women and older adults were more likely to eat more whole grains, while people with lower incomes were less likely to eat more whole grains. The most commonly eaten whole grains in the survey were oatmeal, masa harina, whole wheat bread, corn chips, and wheat crackers.
European Journal of Nutrition. 2021 Jul 7. doi: 10.1007/s00394-021-02635-8.

Following a Mediterranean Diet May Have “Halo Effect” on Other Family Members

Can healthy eating habits rub off on family members who aren’t actively trying to eat better? New research seems to suggest so. In this study, scientists analyzed the diet, weight, and exercise habits of 148 untreated family members of people participating in the PREDIMED-Plus study, a Mediterranean diet weight loss intervention. After two years, the untreated family members lost nearly 9 pounds and scored significantly better on the Mediterranean diet score, indicating a “halo effect” of their family members’ participation in the study. There were no significant changes to the exercise habits of the untreated family members.
International Journal of Obesity. 2021 Jun;45(6):1240-1248. doi: 10.1038/s41366-021-00763-z. Epub 2021 Mar 3. (Zomeño MD et al.)

Plant-Based Diets Linked with Lower Risk of Severe Symptoms in COVID-19

While mask wearing, social distancing, and approved vaccines are thus far the only proven strategies to reduce the risk of contracting COVID-19, research suggests that people with diet-related chronic diseases tend to be at higher risk of having more serious complications if and when they do get COVID-19. In this study of healthcare workers from 7 countries on the front lines of the COVID-19 pandemic (conducted in the summer of 2020, before vaccines became available), those who contracted COVID-19 and reported following a “plant-based diet” or a “plant-based or pescatarian diet” had a 73% and 59% lower risk of moderate-to-severe COVID-19 versus people who did not follow these diets. However, there was no relationship between diet and likelihood of contracting COVID-19.
BMJ Nutrition, Prevention, & Health. 2021 Jun 7;4(1):257-266. doi: 10.1136/bmjnph-2021-000272. eCollection 2021. (Kim H et al.)

Meeting Australian Whole Grain Recommendations in Australia Could Save Over 1.4 billion AUD

Currently, Australian adults are only eating about 21 grams of whole grain per day. In this study, researchers quantified the savings in healthcare and reduction of lost productivity costs associated with a reduction in type 2 diabetes and heart disease through meeting the 48 grams per day whole grain recommendation. If 100% of the Australian adult population were to meet this whole grain goal, researchers estimate a savings of up to 750.7 million Australian dollars (AUD) in healthcare and lost productivity costs for type 2 diabetes, and an additional 717.4 million AUD in healthcare and lost productivity costs for heart disease, totaling more than a 1.4 billion AUD savings. On the low end, even if only 5% or 15% of Australian adults meet the 48 grams per day whole grain goal, there would still be an estimated savings total of 73.4 million AUD to 220.2 million AUD, respectively in healthcare and lost productivity costs related to both conditions.
Nutrients. 2021 May 29;13(6):1855. doi: 10.3390/nu13061855. (Abdullah MMH et al.)

Mediterranean Inspired MIND Diet Linked with Healthier Brain Markers in MS

The Mediterranean diet is well-known for its brain benefits, so scientists wonder how Mediterranean-inspired eating might relate to multiple sclerosis (MS), a brain and spinal cord autoimmune disease. Researchers analyzed the eating habits and brain structures of 180 adults who have had a diagnosis of MS for less than 5 years to see how closely they adhered to a version of the Mediterranean diet called the MIND diet. The MIND diet is a hybrid Mediterranean-DASH diet that emphasizes foods associated with brain health, including whole grains, green leafy vegetables, berries, nuts, olive oil, and fish. In this study, people most closely following the MIND diet had significantly greater thalamic volumes. (The wasting away of the thalamus is a marker of MS disease progression and neurodegeneration, so greater thalamic volume is a good sign that MS might be advancing slower.) Additionally, when looking at specific foods and nutrients, those eating the most full-fat dairy had fewer brain lesions (as measured by lower volumes of T2 lesions) and those eating the most omega-3’s from fish had better microstructural integrity of their normal appearing white matter.
Multiple Sclerosis and Related Disorders. 2021 May 19;53:103031. doi: 10.1016/j.msard.2021.103031. (Katz Sand IB et al.)

Healthy Diet with Sardines Improves Blood Pressure, Weight, Blood Sugar Management

One of the most striking differences between Mediterranean seafood dishes and American seafood dishes is the Mediterranean’s creative use of little fish, like sardines. Researchers randomly assigned 152 older adults (average age: 71) with prediabetes to either a control group with diabetes prevention nutrition advice or an intervention group receiving 7 ounces of sardines per week in addition to diabetes prevention nutrition advice for one year. At the end of the year, both groups lost weight and reduced their waist and hip sizes. Those in the sardine group also improved their blood pressure, blood lipids (such as HDL cholesterol), and insulin resistance (a sign of better blood sugar management). However, there was no significant difference in type 2 diabetes risk between the two groups.
Clinical Nutrition. 2021 May;40(5):2587-2598. doi: 10.1016/j.clnu.2021.03.014. (Díaz-Rizzolo DA et al.)

Mediterranean Diet Linked with Lower Risk of Memory Decline in Elderly

The Mediterranean diet has long been studied for its link with brain health, and now researchers are starting to understand the mechanisms behind this protective relationship. In a study of 512 older adults (average age 69) who were a mixture of people both with and without a family history of Alzheimer’s, researchers found that more closely following a Mediterranean diet was linked with significantly better memory, larger gray matter volume in the area of the brain related to memory (mediotemporal), and less pTau181 (a predictor of Alzheimer’s progression) and amyloid pathology (misfolded proteins in the brain which are associated with Alzheimer’s progression).
Neurology. 2021 May 5;10.1212/WNL.0000000000012067. doi: 10.1212/WNL.0000000000012067.(Ballarini T et al.)

No Link Between Gluten and Brain Health

Misguided dieters may avoid gluten for fear of “grain brain,” and yet research suggests that these fears are unfounded. In a study of 13,494 women without celiac disease, there was absolutely no relationship between gluten and cognitive function. The authors confirm that “restricting dietary gluten for the purpose of maintaining or improving cognition is not warranted in the absence of celiac disease or established gluten sensitivity.”
JAMA Network Open. 2021 May 3;4(5):e2113020. doi: 10.1001/jamanetworkopen.2021.13020. (Wang Y et al.)

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