Health

Most people who follow a balanced diet get enough protein.

Those at risk include older adults, vegans and vegetarians, people with certain autoimmune conditions, and those who take some medications (like metformin or proton pump inhibitors), said Wren Cahoon, a dietitian at UCHealth University of Colorado Hospital.

Fish, red meat

Collagen supplements claim to reduce wrinkles, minimize joint pain and strengthen hair and nails.

It’s easy to get that much from your diet, Dr. Linsenmeyer said.

Aim for two servings per week.

Flax seeds, chia seeds, walnuts, canola oil and soybean oil are also good sources, she said.

If you want to get more omega-3s from your diet, the best sources are fatty fish like salmon, herring, sardines, mackerel and trout, said Whitney Linsenmeyer, an assistant professor of nutrition and dietetics at Saint Louis University.

Many people take vitamin C supplements to strengthen their immune systems or ward off viral infections.

Federal guidelines recommend at least 75 milligrams of vitamin C per day for most women and at least 90 milligrams per day for most men.

Research suggests that people who regularly eat fish — which is rich in omega-3 fatty acids — have better heart health and lower rates of dementia and depression.

Large clinical trials have generally failed to find the same benefits of taking omega-3 (or fish oil) supplements, though one trial suggested a reduced risk of cardiovascular events for people who did not routinely eat much fish.

This includes eating plenty of fruits and vegetables, legumes, nuts and seeds, whole grains, dairy products and healthy sources of protein, she said.

Or incorporate a half-cup of cooked spinach (98 milligrams), black beans (60 milligrams) or quinoa (55 milligrams) into soups or stews.

The more colorful the fruits and vegetables you eat, the wider the range of nutrients you’ll get, said Ethan Balk, a clinical associate professor of nutrition at New York University.

Probiotic supplements contain certain strains of “good” bacteria that are supposed to support a healthy gut microbiome, and prebiotics are substances that feed those good microbes to help them grow.

So unless your doctor recommends them, she advised skipping them.

To support a healthy microbiome (and get essential nutrients in the process), Dr. Oppezzo recommended eating fermented foods like kimchi, sauerkraut, yogurt, kefir and miso.

About half of adults in the United States don’t consume the recommended 310 to 420 milligrams of magnesium per day.

Try adding an ounce of pumpkin seeds (156 milligrams) or an ounce of almonds (77 milligrams) to yogurt or oatmeal.