Nature
Feb 24, 2021 3:20 PM ET
It might be tempting, but it simply isn’t possible to directly compare the effectiveness of vaccines on the basis of those results alone, cautions David Kennedy, who studies the ecology and evolution of infectious diseases at Pennsylvania State University in University Park. Each measure of efficacy comes with a degree of uncertainty, and trials might have differing definitions of important criteria, such as what constitutes a ‘severe’ bout of COVID-19 compared to a ‘moderate’ one.
Added to this are the demographics of each trial: in the case of the Oxford–AstraZeneca vaccine, for example, the developers collected few data about the vaccine’s efficacy in people over 65. This led Germany to authorize the vaccine only for those under 65, even though the European Medicines Agency recommends it for all adults.
Tate Gunnerson, American Heart Association via AP
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Choosing healthy foods can help you cut down on empty calories, in accordance with new federal guidelines.
New federal dietary guidelines encourage Americans to focus more on eating healthy throughout life, to be flexible in their eating patterns and to cut down on empty calories.
The recommendations, released every five years by the U.S. Department of Agriculture and the Department of Health and Human Services, are designed to promote nutrition and prevent chronic disease. The guidance influences food and nutrition programs at the federal, state and local levels, and impacts how food companies formulate their products.
New federal dietary guidelines encourage Americans to focus more on eating healthy throughout life, to be flexible in their eating patterns and to cut down on empty calories.The recommendations, released every five years by the U.S. Department of Agriculture and the Department of Health and Human Services, are designed to promote nutrition and prevent chronic disease. The guidance influences food and nutrition programs at the federal, state and local levels, and impacts how food companies