Why Ezekiel Emanuel wants you to eat your ice cream

In his book, "Eat Your Ice Cream: Six Simple Rules for a Long and Healthy Life," Emanuel recommends a basic, evidence-based approach to maintaining good health, which includes eating ice cream.

"Ice cream will make you happy, and that's very important," he said.

"Ice cream is a good dairy product; it's got protein, its saturated fats are in a globule, so it doesn't affect you as much as saturated fats in meats and other things," he added. "Plus, you typically do it socially with someone else. And you know, being happy is a very important part of living a long time."

Emanuel pointed to evidence showing that people who eat ice cream have a lower risk of metabolic disease, even though ice cream itself has a lot of sugar and fat. Researchers have referred to this phenomenon as the "ice cream paradox."

In a 2005 study, researchers from Harvard University looked at data that followed men between 1986 and 1998 and found that those who had at least two servings of ice cream every week saw a roughly 22% reduced risk of developing diabetes.

Dairy contains whey protein that could benefit glucose regulation, which might explain the association; however, research has yet to establish a cause and effect.

Emanuel's other advice for living a healthy life

Emanuel also strongly recommends getting enough sleep to live a long, healthy life. A new study published this month in the Annals of Internal Medicine found that people who don't get enough sleep for just six weeks start to gain weight, partly because a lack of sleep throws off hunger hormones.

"We know that biologically, sleep is important. We know that it's important to clear out the brain's — to basically empty the garbage, as it were. We know it's important to consolidate long-term memories. We know it's important for DNA to repair. So there's a lot of very important elements," Emanuel said.

Emanuel also recommends against retiring, pointing out that work provides a structure and a schedule, "so you get up and you go. It also provides a mental challenge and a social environment."

"Retiring leads to more rapid cognitive decline for people. I say to people, don't retire," Emanuel added. "And if you're gonna retire, you have to plan retirement well, so that you stay engaged, you stay mentally sharp. And that doesn't mean, 'Well, you know, I'm gonna try to play the saxophone one day.'"

Emanuel's other recommendations include regular movement, especially aerobic exercise that gets your heart rate up and strength training, and avoiding self-destructive risks like smoking, doing drugs, not getting your vaccines, and drinking alcohol.

For alcohol, Emanuel recommends limiting yourself to three or four drinks a week.

"There has been a lot of research on alcohol, so here's the way I distill it: The safest level is probably zero," he said. "There are some studies, and we should be clear, where it's half a cup a day, three cups a week."

"So, you drink every other day," Emanuel added. "On the other hand, 60, 65% of the public drinks. You're not going from 65% to zero. So, you have to give people reasonable advice. And the reasonable advice is, first of all, no binge drinking, that's really bad for you. Don't drink alone. That's really bad for you. If you're using alcohol as a lubricant for social interaction, which many people do, that's probably good; you're getting some benefit from the social interaction."