A lot of time, energy, and resources have been spent over the last few decades trying to educate people about the role of dietary fat in cardiovascular disease. Food manufacturers went to work removing fat from their foods, but they had to add something else to replace the flavor. And that "something else" was sugar.

The average American consumes 22 teaspoons of sugar each day or about 152 pounds a year. About 75 percent of grocery store items have added sugar. Now it appears that all this sugar may be a culprit in heart disease.

It is likely that recommendations for sugar intake will be changing, forcing the food industry to reconsider the addition of sugar to everything from frozen pizza to coleslaw to barbecue sauce to instant oatmeal while claiming that added sugars are risk free.

Researchers conducted a review and meta-analysis of dozens of international studies published between 1965 and 2013 that examined the effect of sugars and non-sugar carbohydrates on blood pressure and blood lipids.

After combining the results of all the studies, Dr. Lisa Te Morenga and her colleagues found that sugar appeared to be a contributing factor to cardiovascular risk, whether or not it makes a person gain weight.

According to Te Morenga, “Although the effects of sugars on blood pressure and lipids are relatively modest, our findings support public health recommendations to reduce added sugar in our diets as one of the measures which might be expected to reduce the global burden of cardiovascular disease.”

Previous research had not indicated that sugars made people metabolically more likely to gain weight on a high-sugar diet versus a low-sugar diet, as long as the amount of carbohydrates and calories were the same. But the new study found differently.

“[O]ur latest study did find significant effects of sugars on lipids and blood pressure among those types of energy-controlled studies. This suggests that our bodies handle sugar differently to other types of carbohydrates,” said Te Morenga, a professor in New Zealand's University of Otago’s Department of Human Nutrition.

Many of the studies reviewed by the researchers were funded by the food industry. Such trials are not as likely to find a significant association between sugars and adverse health problems. When those studies were excluded, sugar had an even larger effect on blood lipids and blood pressure.

There seems to be no universally-accepted recommendation for sugar consumption. The Institute of Medicine suggests that added sugar should make up less than 25 percent of daily calories.

The World Health Organization recently issued a draft proposal halving its recommendation for sugar intake from 10 percent of total calories to 5 percent. The current Dietary Guidelines for Americans recommend keeping the intake of added sugars to a minimum.

The American Heart Association recommends that women consume no more than 100 calories a day from added sugar (6 teaspoons), and men should limit their sugar intake to 150 calories a day (9 teaspoons). Children should be limited to 3 to 4 teaspoons per day, depending on their age.

As the World Health Organization reviews comments on their draft proposal and experts are working on the 2015 Dietary Guidelines for Americans, it is likely that recommendations for sugar intake will be changing, forcing the food industry to reconsider the addition of sugar to everything from frozen pizza to coleslaw to barbecue sauce to instant oatmeal, while claiming that added sugars are risk free.

The study is published in the Journal of Clinical Nutrition.