Everyone needs protein — it's vital for the growth, repair and maintenance of your muscles, bones and skin. But how much you need depends on your age, weight and nutritional needs. Despite the increasing range of protein-enriched foods on the market, experts say if you're getting enough to eat, you are probably getting enough protein. Protein can be found in a wide variety of foods, including meat, dairy and plant-based foods.

A National Institutes of Health study aims to find out whether ultraprocessed foods lead people to eat more. And, if so, why? Teasing out the answers could shed light on the controversial fare that makes up more than 70% of the U.S. food supply. Ultraprocessed foods are linked to ailments including obesity and diabetes, but it's not clear exactly how. Addressing chronic disease is a key goal of the "Make America Healthy Again" agenda embraced by President Donald Trump and Health Secretary Robert F. Kennedy Jr. Scientists say such research is difficult, time-consuming — and expensive.

Ultraprocessed foods make up the bulk of the U.S. food supply and most Americans don't go a day without eating some. The foods include sugary cereals, frozen dinners, soda, potato chips and ice cream. They've been linked to a host of negative health effects from obesity and diabetes to heart disease, depression, dementia and early death. But most research has found links, not proof, for those health consequences, making it difficult to target specific foods for reform or regulation. Food manufacturers argue that processing boosts food safety and supplies and offers a cheap, convenient way to provide a diverse and nutritious diet.