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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.)

Vegetarian Diets Linked with Lower Risk of Cancer

Cancer is one of the leading causes of death worldwide, yet there is still much to learn about cancer prevention strategies. In an 11-year study of nearly half a million adults in the U.K., researchers found that people who ate pescatarian diets (fish but no meat), vegetarian diets (no meat or fish), and smaller than usual amounts of meat (5 or fewer servings per week) had a significantly lower risk of all cancers compared with regular meat eaters. There was also a lower risk of colorectal cancer for reduced meat eaters, and postmenopausal women who consumed less meat or fish also had a reduced risk of breast cancer. More research is needed to better understand the relationship between diet, lifestyle, and cancer risk.
BMC Medicine. 2022 Feb 24;20(1):73. doi: 10.1186/s12916-022-02256-w. (Watling CZ et al.)

Transitioning High-Income Nations to Climate-Friendly Diet Could Substantially Benefit Environmental Health

High income nations tend to have diverse food options that are disproportionally based on high-carbon footprint foods like meat and could be a great starting point when considering where to introduce climate-friendly diets. In this study, researchers used models to determine that if 54 high-income nations shifted to the EAT-Lancet diet (a primarily plant-based, healthy diet) and restored the resulting spared land to natural vegetation, they would have the potential to reduce their carbon emissions by 61%, which is equivalent to 14 years’ worth of current global agricultural emissions.
Nature Food. 2022 Jan 10;3:29-27. doi: 10.1038/s43016-021-00431-5. (Sun Z et al.)

Plant-Based Diets Tend to Be More Affordable and Sustainable

As stress on our food system increases, certain dietary patterns may increase harmful environmental impacts. Diets that are nutritious and sustainable, such as those low in animal products and higher in plant-based foods, have been proposed as a solution to this issue which still meets dietary needs. In this study, researchers analyzed 150 different dietary patterns from varying countries and regions by pairing an estimate of food demand with an estimate of commodity prices in different years, with consideration of any food-system and socioeconomic changes. Across the dietary patterns sampled, the most affordable and sustainable were vegan/vegetarian diets that replaced meat with legumes or whole grains. The least affordable were pescetarian diets that centered around fish, fruits, and vegetables. Staple crops, such as cassava, maize, plantains, potatoes, rice, soybeans, sweet potatoes, and wheat, tend to be the most affordable aspect of these dietary patterns. Household food waste accounted for 29% of all food costs, so helping people to reduce food waste could improve both affordability and environmental sustainability.
Lancet Planetary Health. 2021 Dec;5(12):e861. doi: 10.1016/S2542-5196(21)00316-8. Epub 2021 Nov 24. (Springmann M et al.)

Healthy, Plant-Based Diets Linked with Lower Greenhouse Gas Emissions

Food production accounts for roughly ⅓ of total greenhouse gas emissions, meaning that small shifts in food choices can make a big impact. In this study, researchers calculated the greenhouse gas emissions of 3,233 different foods, as well as example diets from 212 adults. In general, diets that are better for people also tended to better for the planet. For example, people who kept to the recommended levels of sodium, saturated fat, and carbohydrates had lower greenhouse gas emissions than those who exceeded those levels. Further, non-vegetarian diets produced 59% more greenhouse gas emissions than vegetarian diets. When looking at individual food categories, 32% of diet-related greenhouse gas emissions were from meat, 15% from drinks, 14% from dairy, and 8% from cakes/cookies/confectionary.
PLoS One. 2021 Nov 23;16(11):e0259418. doi: 10.1371/journal.pone.0259418. (Rippin HL et al.)

Healthy Plant-Based Foods Associated with Lower Risk and Severity of COVID-19

While vaccines, masks, and social distancing are still the most effective strategies to prevent COVID-19, researchers wonder if diet might also be related to susceptibility of contracting the disease. In this study, researchers analyzed the diets of 592,571 people and followed them to see whether or not they contracted COVID-19. Those whose diets scored best on the healthful Plant-Based Diet Score (a measure of how many healthy plant-based foods people eat, such as fruits and vegetables) were 9% less likely to develop COVID-19 and were 41% less likely to develop severe COVID-19. Additionally, the relationship was strongest in people living in poorer areas.
Gut. 2021 Nov;70(11):2096-2104. doi: 10.1136/gutjnl-2021-325353. Epub 2021 Sep 6. (Merino J et al.)

Whole Grains Are an Underutilized Source of Plant Protein

Although grains are a large source of plant protein in many African, Central American, Asian, and European nations, grains are not considered an important source of protein in any dietary guidelines around the world. In this review, scientists analyze the unused potential of whole grains as animal protein alternatives. Although research suggests that consuming grains as the sole source of protein could result in deficiency, and although grains have a lower protein content than beans and other pulses, shifting grains away from animal feed and toward direct human consumption could be an important strategy to improve both human and environmental health. The review notes that both high whole grain intake and high plant-protein intake have been associated with lower risks of chronic diseases, while high animal protein intake has been associated with higher risks of disease. The authors also highlight processing strategies, such as mixed culture fermentation, that can help improve consumer acceptance of whole grain meat and dairy replacement products.
Nutrition Reviews. 2021 Nov 6;nuab084. doi: 10.1093/nutrit/nuab084. (Poutanen KS 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.)

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.)

Plant Based Diets Can Lower Blood Pressure

Studies have shown that plant-based diets can help lower blood pressure, but researchers wonder how strict you must be with your vegetarian diet to see results. A systematic review of 41 clinical trials was performed to see how different plant-based diets, including some with low levels of animal products (the Mediterranean, Vegan, Nordic, high-fiber, and high-fruit and vegetable diets) impacted blood pressure. The results showed that even plant-based diet with limited animal products can be effective in reducing high pressure, indicating that even small steps to improve health can make a measurable difference. 
Journal of Hypertension. 2021 Jan;39(1):23-37. doi: 10.1097/HJH.0000000000002604. (Gibbs, al)

Mediterranean Diet Linked with Better Thyroid Health

Our thyroids act as internal thermostats providing our bodies with hormones that help balance our heart, muscle, and digestive function, brain development, and bone maintenance. In this study, researchers analyzed the eating habits and health of 200 people, about half with Hashimoto’s Thyroiditis (an autoimmune disease that attacks the thyroid) and half without. Those most closely following a Mediterranean diet were less likely to have Hashimoto’s Thyroiditis. Eating more animal foods (like meat) and fewer plant foods (like vegetables) was also linked with Hashimoto’s Thyroiditis.  However, more research is needed on how diet might impact autoimmune and thyroid health.
Thyroid. 2021 Jan;31(1):96-105. doi: 10.1089/thy.2020.0299. (Ruggeri RM et al.)

Vegetarian Diets Linked with Lower Risk of Cataracts

Cataracts contribute to more than half of the blindness incidences globally. Diets with more antioxidants are thought to help prevent cataracts, so in this study, researchers wanted to see how vegetarian diets relate to cataract risk. A total of 4,436 Taiwanese participants (1,341 vegetarians and 3,095 non-vegetarians) free of cataracts at the time of recruitment were followed for approximately six years. After evaluating the development of cataracts among all participants, the researchers discovered that vegetarians had a 20% lower risk of cataracts than non-vegetarians. This relationship was strongest among people whose BMI is greater than 24 (overweight and nearly overweight individuals). Vegetarians tend to consume more soy, vegetables, nuts, whole grains, dietary fiber, vitamin C, folate, and vitamin A compared to non-vegetarians, so these nutritious foods and nutrients may have also impacted the lower risk of cataracts. 
Journal of the Academy of Nutrition and Dietetics. 2020 Dec 11;S2212-2672(20)31428-3. doi:10.1016/j.jand.2020.11.003 (Chiu THT et al.)