Image copyright AFP Image caption The panel stopped of recommending a vegetarian only diet

Americans should eat a diet higher in plants, fruits and grains because it is healthier and has a lower environmental impact, a US panel has said.

The report by medical and nutrition experts will be considered in the US dietary guidelines which determine school lunches to food package labels.

Cholesterol is now less of a concern, the report said, but added sugar should be limited to 200 calories a day.

The panel also backs moderate coffee drinking for the first time.

The Dietary Guidelines Advisory Committee, which meets every five years, said a diet high in vegetables, fruits, grains, legumes, nuts and seeds was "more health promoting and is associated with less environmental impact'' than the current US diet, which is high in meat.

It is the first time the panel has made a recommendation on the environmental impact of a diet.

Image copyright AP

But their report stops short of telling people to be completely vegetarian, saying "no food groups need to be eliminated completely to improve sustainability outcomes".

The panel also backs away from a prior guideline to limit dietary cholesterol, in particular egg consumption.

The report now says the available evidence "shows no appreciable relationship" between heart disease and how much dietary cholesterol you eat, but still recommends eating less saturated fat.

Responding to concerns about caffeine for the first time, the panel said there was "strong evidence" that three to five cups a day can be part of a healthy diet, including reduced risk of diabetes and heart disease.

The panel recommended pregnant women limit caffeine to two cups of coffee a day.