Blood pressure reading

Eating foods with too much phosphate, a common food and beverage additive, increased blood pressure in rats, particularly during exercise, a recent study showed.

It’s a finding that if confirmed would support the Food and Drug Administration including the amount of added phosphate on food labels, researchers said.

Three months of eating a high-phosphate diet led rats to have a higher blood pressure at rest and a greater rise in blood pressure and sympathetic nerve activity during exercise than in rats consuming recommended amounts of phosphate.

The sympathetic nervous system turns on the body’s fight-or-flight response to stress, which includes exercise.

Blood pressure rises naturally during exercise, but too much of an increase can up the risk of a heart attack, stroke and thickening of the heart’s walls, study coauthor Wanpen Vongpatanasin, M.D., of the University of Texas Southwestern Medical Center in Dallas, said in a news release.

Because exercise is often recommended to control high blood pressure, having blood pressure go too high would limit the use of exercise as a treatment option, study coauthor Scott Smith, Ph.D., of UT Southwestern, said in a news release.

Phosphate is naturally found in whole grains, unprocessed meat and milk. It contributes to strong bones and teeth, muscle contraction and nerve function. But food manufacturers use phosphate additives to boost flavor and preserve color in processed meat, cheese, salad dressings, beverages and baked goods.

Most Americans consume twice the recommended amount of phosphate, Vongpatanasin said.

“Our findings may have relevance in terms of raising safety concerns regarding long-term consequences of phosphate additives in our diet,” Vongpatanasin said.

The study was published in the American Journal of Physiology—Regulatory, Integrative and Comparative Physiology.