Not many people know about the Harvard diet, which has been created as an eating guide for optimal health.

Also called the healthy eating plate, the Harvard diet was conceptualized in 2011. For formulating the ultimate diet plan, experts at the Harvard T.H. Chan School of Public Health worked in collaboration with researchers from Harvard Health Publications.

“In terms of major chronic diseases like prevention of cardiovascular disease, different types of cancers [and] Type 2 diabetes, this way of eating is going to be helpful to prevent those diseases that are common in America, and the world,” said Lilian Cheung, lecturer of nutrition at Harvard’s school of public health, CNBC reported.

The Healthy Eating Plate can be used as a guide for "creating healthy, balanced meals—whether served at the table or packed in a lunch box" as per Harvard’s website.

Here are the six pointers to follow the Harvard diet

Vegetables and fruits--half of the plate

Fruits and vegetables should make up half of a person’s plate. Researchers suggest aiming “for color and variety” as well as eating vegetables more than fruits.

Also, be careful what constitutes a vegetable. For instance, “a potato is not a vegetable from a nutrition point of view,” Cheung explained. “Potatoes almost behave like a refined carbohydrate. It increases your blood sugar.”

The nutrition expert also recommended consuming whole fruits over juices.

Whole grains--a quarter of the plate

The diet plan encourages eating whole grains and not refined grains.

“Whole grains have much more vitamins and also phytochemicals and minerals, which is much healthier for us and won’t raise [our] blood sugar so fast,” Cheung said, according to the news outlet.

A few options to consider include oats, quinoa, barley, whole wheat, and brown rice.

Protein--a quarter of the plate

The healthy eating plate suggests the type of proteins to consume, and the ones to ignore.

Healthy proteins like fish, chicken, beans, nuts, and duck should make up a quarter of your plate.

Avoid red meat and steer clear of processed meats like bacon and sausage, Cheung suggested.

Plant oils--in moderation

The Harvard diet asks to avoid trans fats such as partially hydrogenated oils like margarine and certain vegetable oils. Healthier options include oils made from olive, canola, soy, corn, sunflower, and peanut (if not allergic).

Drink water, tea, or coffee

“We were really deliberate in terms of the drinks,” says Cheung.

“We didn’t think that it was the most prudent way to go about it, especially because there are some populations in the U.S. that are lactose intolerant,” said Cheung of the notion that people should drink three cups of milk each day.

“Even with just the amount of calories from drinking [milk] that way, it would be more preferable to be drinking water, tea, or coffee,” Cheung further said.

The diet recommends drinking water, tea, and coffee alternatively with one’s meals, while also keeping sugar in the beverages little to none.

Stay active

The eating plan is incomplete without physical activity. “We need to be engaging [for] half an hour a day, or at least five times a week, in vigorous activity,” Cheung noted.

“We’re all aging, and we should form good habits while we are young,” Cheung continued, “so they become part of our habit and our routine.”