Viviane Lester participated in a recent study that confirmed what she'd already been told by her family doctor about her salt intake. (Julia Kilpatrick/CBC)

A gene could be responsible for the high blood pressure some people experience after eating a lot of salt, say researchers at the University of Ottawa Heart Institute.

The researchers are conducting a study in which participants with high blood pressure will be asked to dramatically increase and then decrease the amount of salt in their diets.

When certain participants' blood pressure goes up along with their sodium chloride intake, the researchers will flag them, test them and compare their genes.

If there's a similarity in their genes — one that doesn't exist in participants who don't have a sodium sensitivity when it comes to their blood pressure — the researchers will note that as a possible "salt gene."

If the study is successful, people concerned that they might be predisposed to sodium-influenced high blood pressure could arrange a genetics test.

A chance to change

Viviane Lester, who took part in the study, said that test would give some people a chance to change their diets before health problems appear.

She said she never used to pay attention to the labels on packaged food, but had to when she found out that salt was raising her blood pressure.

"You can't eat sauces, baked goods. Eating out is very difficult — even McDonald's is hard because you can't eat a cheeseburger and French fries … all the fun things in life."

Dr. Frans Leenen, who works in the institute's hypertension unit and heads the university study, said high blood pressure is sometimes only the beginning for patients.

"High blood pressure is a major cause of strokes and heart attacks," Leenen said. "If we can prevent that or prevent having to take medication for many years to treat high blood pressure, I think that is the way to look at it."

Leenen said that finding out if a gene can indicate salt sensitivity will help researchers design more targeted medications and also help people with high blood pressure know if reducing salt intake will have any effect.

Lester said participating in the study confirmed what she'd been told for years.

"I had been told by my family doctor to cut my salt intake," she said. "And like most people, I said, 'OK, I'll quit adding salt and I'll quit eating potato chips and pretzels."

Only half of people who have high blood pressure, said Leenen, are sensitive to salt.