Effect of a Plant-Based vs Omnivorous Soul Food Diet on Weight and Lipid Levels Among African American Adults: A Randomized Clinical Trial.

Importance: More African American individuals die from cardiovascular disease (CVD) than any other chronic disease condition. Despite this disparity, African American individuals are underrepresented in nutrition and CVD interventions. Objective: To compare the effects of an entirely plant-based (vegan) or low-fat omnivorous (omni) diet on change in body weight and lipids during a 2-year intervention. Design, Setting, and Participants: The Nutritious Eating With Soul (NEW Soul) study was a 2-year, randomized clinical trial conducted in 2 cohorts (2018-2020 and 2019-2021) that took place in a university teaching kitchen in Columbia, South Carolina (before March 2020), and via online videoconference sessions (after March 2020). Participants included African American adults aged 18 to 65 years with overweight or obesity (body mass index of 25.0-49.9) and without type 2 diabetes, uncontrolled thyroid disease, recent weight loss, or pregnancy. Data assessors and statisticians were blinded to study condition. Data analysis was performed from March to June 2022. Interventions: The intervention included weekly nutrition classes for 6 months biweekly classes for 6 months, and monthly classes for 12 months. Dietary interventions either emphasized no animal product intake (vegan) or a low-fat omnivorous diet (omni). Both dietary patterns emphasized soul food cuisine (traditional African American southern foodways). Main Outcomes and Measures: Primary outcomes included change in body weight and lipid measures at 12 months. Results: There were 568 participants who completed an online screening questionnaire; 409 were excluded and 159 were randomized (77 to the vegan group and 82 to the omni group). Of the 159 participants (mean [SD] age, 48.4 [10.6] years; 126 female [79%]) who began the study, the main outcome of body weight was obtained for 121 participants (76%) at 12 months. There were no differences in outcomes between groups, including 12-month changes in weight (mean, -2.39 kg [95% CI, -3.48 to -1.30 kg] for the vegan group vs -2.03 kg [95% CI, -3.07 to -1.00 kg] for the omni group; P = .64), total cholesterol (-1.05 mg/dL [95% CI, -9.60 to 7.50 mg/dL] for the vegan group vs 1.66 mg/dL [95% CI, -7.20 to 10.50 mg/dL] for the omni group; P = .67), or low-density lipoprotein cholesterol (mean, -2.56 mg/dL [95% CI, -9.52 to 4.40 mg/dL] for the vegan group vs -0.79 mg/dL [95% CI, -7.98 to 6.40 mg/dL] for the omni group; P = .73). Weight loss at 12 months among cohort 1, whose weight was assessed in 2019 before the COVID-19 pandemic, was significantly greater than that for cohort 2, whose weight was assessed summer 2020 during COVID-19 (-3.45 kg [95% CI, -4.67 to -2.22 kg] vs -1.24 kg [95% CI, -2.24 to -0.25 kg]; P = .01). Conclusions and Relevance: In this randomized clinical trial examining weight loss and CVD risk factor reduction among African American adults, there were no differences between the groups, and the magnitude of changes overall was small. Trial Registration: ClinicalTrials.gov Identifier: NCT03354377.

Modifiable Host Factors for the Prevention and Treatment of COVID-19: Diet and Lifestyle/Diet and Lifestyle Factors in the Prevention of COVID-19.

Many studies have shown that the immune system requires adequate nutrition to work at an optimal level. Not only do optimized nutritional strategies support the immune system, but they also reduce chronic inflammation. Nutritional supplements that are recommended for patients with critical illnesses are thought to also be effective for the coronavirus disease 2019 (COVID-19) patients in the intensive care unit. Some studies have recommended fresh fruits and vegetables, soy, nuts, and antioxidants, such as omega-3 fatty acids, to improve immune system activity. Although nutritional status is considered to be an important prognostic factor for patients with COVID-19, there is to date no sufficient evidence that optimal nutritional therapies can be beneficial for these patients. Some have argued that the COVID-19 pandemic is a good opportunity to test the effectiveness of nutritional intervention for infectious diseases. Many researchers have suggested that testing the proposed nutritional approaches for infectious diseases in the context of a pandemic would be highly informative. The authors of other review papers concluded that it is important to have a diet based on fresh foods, such as fruits, vegetables, whole grains, low-fat dairy products, and healthy fats (i.e., olive oil and fish oil), and to limit the intake of sugary drinks as well as high-calorie and high-salt foods. In this review, we discuss the clinical significance of functional food ingredients as complementary therapies potentially beneficial for the prevention or treatment of COVID-19. We believe that our review will be helpful to plan and deploy future studies to conclude these potentials against COVID-19, but also to new infectious diseases that may arise in the future.

Adaptation of fuel selection to acute decrease in voluntary energy expenditure is governed by dietary macronutrient composition in mice.

In humans, exercise-induced thermogenesis is a markedly variable component of total energy expenditure, which had been acutely affected worldwide by COVID-19 pandemic-related lockdowns. We hypothesized that dietary macronutrient composition may affect metabolic adaptation/fuel selection in response to an acute decrease in voluntary activity. Using mice fed short-term high-fat diet (HFD) compared to low-fat diet (LFD)-fed mice, we evaluated whole-body fuel utilization by metabolic cages before and 3 days after omitting a voluntary running wheel in the cage. Short-term (24-48 h) HFD was sufficient to increase energy intake, fat oxidation, and decrease carbohydrate oxidation. Running wheel omission did not change energy intake, but resulted in a significant 50% decrease in total activity and a ~20% in energy expenditure in the active phase (night-time), compared to the period with wheel, irrespective of the dietary composition, resulting in significant weight gain. Yet, while in LFD wheel omission significantly decreased active phase fat oxidation, thereby trending to increase respiratory exchange ratio (RER), in HFD it diminished active phase carbohydrate oxidation. In conclusion, acute decrease in voluntary activity resulted in positive energy balance in mice on both diets, and decreased oxidation of the minor energy (macronutrient) fuel source, demonstrating that dietary macronutrient composition determines fuel utilization choices under conditions of acute changes in energetic demand.