Whole grains were linked to a lower risk of death, type 2 diabetes, cardiovascular disease, obesity and possible even colorectal cancer, said the International Carbohydrate Quality Consortium (ICQC).
Eating about two servings a day, or 16g dry weight of whole grains, was enough to get the health benefits, they added.
They are a quality source of fibre and nutrients in the diet, and there was a need to communicate their benefits to the public and health professionals, the ICQC said.
Strong research supported the claim that whole grain consumption reduced the risk of death, the non-profit worldwide organisation said.
The committee’s only UK academic, Dr Marie-Ann Ha of Anglia Ruskin University, said: “Grains are the major source of carbohydrates globally, but the quality of these grains is vital to ensure a healthy diet.
“The ICQC [believe it’s] important to promote healthy eating and lower the risk of obesity and disease.
“We need to determine the difference between intact whole grains, like brown rice, and milled whole grains, such as those found in wholemeal bread and pasta.
“Both have a positive effect on health, but the question of how exactly these respective benefits are seen requires more research.”
Whole grains, as opposed to refined grains – white rice, white bread, white pasta and products made with white flour – provided important health benefits.
Studies claimed the grains – particularly cereal fibre – played a big role in reducing the risk of colorectal cancer.
An upper limit on the amount of whole grains recommended wasn’t clear, said the ICQC.
Further studies were needed to confirm their health benefits, they said. Research should focus on glucose and insulin responses to the grains, and whether individual types of grain had more or less health benefits than others.
Meanwhile, this month a Danish study revealed eating more whole grain foods reduces inflammation in the body.
Excess inflammation could increase the risk of developing type 2 diabetes.
Rye had the largest anti-inflammatory effect, the study claimed.
Whole grain foods include wheat, rye, barley, oats, brown and red rice, millet and corn.