Ask a Doctor: 10 tips to help you live better

Chelsea Conrad/The Washington Post/iStock (Chelsea Conrad/The Washington Post/iStock)

Every week on Well+Being, we ask a doctor to answer one of your questions. Here are the 10 most popular questions you asked in 2022, with a summary of the health advice our doctor writers shared.

1. How much vitamin D do I need?

By JoAnn E. Manson, MD

Large, randomized clinical trials over the past few years have shown that vitamin D isn’t the panacea some believed it to be. The bottom line: The vast majority of Americans are getting all the vitamin D they need from their diet and the sun.

Is it necessary for you to spend money on the supplement? For most healthy adults, the answer is no. We need only small-to-moderate amounts of the vitamin, and more is not necessarily better.

2. What treatments work for women with thinning hair?

By Jennifer N. Choi, MD

Topical minoxidil, often known by the over-the-counter brand name of Rogaine, is my first go-to treatment for the most common cause of thinning hair in women: female androgenetic alopecia (AGA). If you’ve noticed hair loss, the first step you should take is getting a diagnosis from a primary care physician or a dermatologist, who may do a scalp biopsy and order bloodwork to look for potential causes, such as anemia or thyroid disorders. If your hair loss has been gradual and started as widening at your part, with your frontal hairline still intact, you probably have AGA.

3. Are salads really good for you?

By Robert H. Lustig, MD

Salad is usually a healthy food, but only if you add the right combination of ingredients and stay away from store-bought bottled dressing. It may surprise you to learn that the type of greens you choose doesn’t really matter that much. The main health benefit of lettuce and other greens in a salad is the fiber. Salads are usually packed with fiber, which is really food for the microbiome, the trillions of bacteria that live in your gut and the key to metabolic health.

To make a great homemade dressing, focus on ingredients such as extra virgin olive oil, avocado oil, tahini, vinegar, Dijon mustard, herbs, spices and citrus juices low in sugar (lemon, lime, grapefruit).

4. Why do I get sleepy in the afternoon after eating lunch?

By Lydia Kang, MD

Feeling sluggish after lunch is very common. The “afternoon dip,” as it’s sometimes called, refers to those groggy hours between 2 p.m. and 5 p.m., when your eyelids droop and your concentration becomes as sharp as vanilla pudding.

There can be myriad reasons this happens, including too little sleep at night or medical conditions such as obstructive sleep apnea, anemia and thyroid disorders. If you feel exhausted, check with your health-care provider to make sure all is well. Pack a lunch full of veggies, which are rich in fiber and can help regulate your blood sugar. Avoid consuming a large portion of animal protein and fat. Try eating complex carbohydrates such as whole grains and legumes, and veer away from simple carbs, including sugary drinks and white pasta. A brisk walk, ideally outside, can also give you a boost.

5. Why do I pee so much at night?

By Petar Bajic, MD

Nighttime urination, also known as nocturia, can affect men and women at any age. The more common causes are entirely benign, though nocturia can also be triggered by certain health conditions and medications.

In my practice, patients are often shocked to learn that sleep apnea can be the underlying cause of their nocturia. Nocturia can also be a warning sign for other health conditions, such as diabetes, heart failure, urinary tract infections and an overactive bladder, as well as a reaction to some medications, including those used to treat hypertension and kidney conditions. Sometimes, it’s linked to other sleep issues, such as insomnia.

6. Is marijuana as bad for me as alcohol?

By Salomeh Keyhani, MD

We have decades of research on the health effects of drinking. But research on cannabis is evolving, and the public health consequences of its commercialized use — in new products and doses — will take years to understand.

From a medical standpoint, there is no level of alcohol use that is completely safe, as studies have shown harms even with light drinking. In terms of cannabis, I tell my patients that we still aren’t sure if there is a safe level of use, but that in general, scientists consider frequent and higher-THC use to be riskier.

7. Why do I twitch before falling asleep?

By Mark Wu, MD

Most people think of sleep and wakefulness as two different states of being, but there are moments in which the lines between them blur. During this transition, as you drift off to sleep, you might feel a twitch that jolts you awake.

These twitches — known as hypnic jerks or sleep starts — involve brief contractions of one or multiple muscles and can be accompanied by other sensations, such as the feeling of falling. Humans aren’t the only ones who experience them: Dogs also twitch when they fall asleep.

These experiences are quite common and rarely are a cause for concern. They can be provoked or exacerbated by stress, sleep deprivation and excessive caffeine use.

8. Is animal protein easier to absorb than plant protein?

By Walter Willett, MD

The proteins in foods from animals, such as meat, milk and eggs, tend to be absorbed more easily than those from plant sources, such as nuts, beans and grains. This is partly because of the fibrous coatings that help protect plants from insects and diseases, and this shield can also reduce the rate of digestion.

But this isn’t a reason to choose animal proteins over plant proteins. The difference in absorption is minor, typically about 10 to 20 percent lower from plants than from animals, and it would only be a concern if our diets had barely enough protein to meet requirements. For adults in the United States and other affluent countries, protein intake is usually above what we need — about 15 percent of daily calories on average — so the difference in absorption between animal and plant proteins is largely inconsequential.

9. What’s the best way to get rid of blackheads?

By Jenna C. Lester, MD

Although it’s tempting, squeezing blackheads with your fingers is a bad idea. That can cause trauma to the skin and lead to hyperpigmentation or scarring.

You can try topical treatments, which will take longer to work but are cost-effective and will do the most for you in the long run, since they can prevent future blackheads from forming. They’re also readily available at most drugstores and at a variety of price points, so you can find the best option for your budget and skin.

10. What happens if I drink too much water?

By Joseph G. Verbalis, MD

The most likely outcome is just that you’ll urinate more frequently to get rid of the excess water.

But it is possible to go overboard. Normal kidneys can release up to a quart of fluid every hour. If you drink more than that, you’ll retain the excess water in your body, which causes a condition known as hyponatremia and can be hazardous to your health.

Hyponatremia was the cause of death in a participant in a 2007 radio contest in California, in which the prize went to whoever could drink the most before having to urinate. Excessive water intake also has led to the deaths of students during fraternity hazing rituals. But it’s important to remember that these are contrived situations that most people would never experience. The bottom line: If you don’t feel thirsty, chances are you’re properly hydrated. But if you do feel thirst, drink as much as you need until the thirst goes away.