Eating breakfast is the secret to staying healthy, according to evidence unearthed by doctors in the US.
Some foods may have greater health benefits
They believe skipping the first meal of the day increases the chances of becoming obese, developing diabetes or even having a heart attack.
Their study found that people who eat whole-grain cereals every morning are among those most likely to see the health benefits.
Dr Mark Pereira and colleagues at Harvard Medical School analysed the eating habits of 1,198 black people and 1,633 white participants.
Overall, 47% of whites and 22% of blacks said they ate breakfast every morning.
They found that people who ate breakfast every day were a third less likely to be obese compared to those who skipped the meal.
In addition, they were half as likely to have blood-sugar problems, which increase the risk of developing diabetes or having high cholesterol, which is a known risk factor for heart disease.
The researchers believe that eating first thing in the morning may help to stabilise blood sugar levels, which regulate appetite and energy.
Breakfast may really be the most important meal of the day
They suggest people who eat breakfast are less likely to be hungry during the rest of the day and are, therefore, less likely to overeat.
"Our results suggest that breakfast may really be the most important meal of the day," said Dr Periera.
"It appears that breakfast may play an important role in reducing the risk of type 2 diabetes and cardiovascular disease."
The researchers have recently started to examine what those involved in the study ate for breakfast, to see if certain foods were more likely to help them stay healthy.
Initial results have suggested that whole-grain cereals may be of benefit.
They found that people who ate these were 15% less likely to have blood sugar problems but Dr Pereira said: "We need to do more research."
The British Dietetic Association said the findings added to the growing body of evidence in support of eating breakfast every morning.
"There is a lot of scientific evidence behind this," spokeswoman Catherine Collins told BBC News Online.
"Obviously the traditional fry-up is too fat and calorie rich to aid weight control, but cereals and toast are of benefit.
"Breakfast can be a very good source of vitamins. Many processed cereals are fortified with vitamins and minerals which people can find it difficult to get elsewhere if they are just having two meals a day."
The study was presented at the American Heart Association's annual conference in Miami.