We’ve heard time and again about the effects of high-sodium diets on our health. While many people are worried about fat, calories, and sugar — and rightfully so — others are worried about how much sodium they’re consuming. After all, the average American eats about 1,000 milligrams more sodium than they should each day. Though it’s important for the healthiest of people to make the effort to eat recommended amounts of sodium, it’s even more important for diabetics to not overdo it.

A new study by Japanese researchers has found just how important a low-sodium diet is for diabetics — those who ate lots of salt were twice as likely to develop cardiovascular disease as those who ate less. “The study’s findings provide clear scientific evidence supporting low-sodium diets to reduce the rate of heart disease among people with diabetes,” said study author Chika Horikawa, a registered dietician from the University of Niigata Prefecture in Niigata, Japan, in a press release. “Although many guidelines recommend people with diabetes reduce their salt intake to lower the risk of complications, this study is among the first large longitudinal studies to demonstrate the benefits of a low-sodium diet in this population.”

The findings are particularly relevant to Japanese and other Asians, whose diets typically consist of high-sodium foods and sauces, such as soy and fish sauce. One tablespoon of soy sauce contains 879 milligrams of sodium, according to the U.S. Department of Agriculture (USDA). That’s more than one-third of the daily recommended value. By cutting the amount of sodium they eat, diabetics can reduce their blood pressure, as the kidneys are better able to draw unwanted fluids out of the blood. In turn, a lower blood pressure leads to a lower risk of heart attack and stroke.

The researchers surveyed 1,588 participants, ages 40 to 70, who were part of the Japan Diabetes Complications Study. All patients had diabetes and were asked about their diets and sodium intake. Over the next eight years, the researchers kept up with the participants to see who developed cardiovascular complications. They found that, on average, those who ate about 3 grams of sodium daily — still more than the recommended daily value of 2.3 grams — had half the risk as those who ate 5.9 grams of sodium daily of developing heart disease. The risk of developing heart disease became even worse when participants had trouble controling their blood sugar levels.

“To reduce the risk of developing cardiovascular disease, it is important for people who have type 2 diabetes to improve their blood sugar control as well as watch their diet,” Horikawa said. “Our findings demonstrate that restricting sale in the diet could help prevent dangerous complications from diabetes.”

Over 29 million Americans had diabetes in the U.S. in 2012, according to the American Diabetes Association. In addition to them, an estimated 1.7 million new cases are diagnosed each year. Diabetes is the seventh leading cause of death in the country, being implicated in as many as 300,000 deaths in 2010 alone.

Source: Horikawa C, Yoshimura Y, Kamada C, et al. Dietary Sodium Intake and Incidence of Diabetes Complications in Japanese Patients with Type 2 Diabetes. Journal of Clinical Endocrinology & Metabolism. 2014.