Refined grains and your heart: a primer

Most of the six to seven helpings of grains many of us eat daily are refined. Choosing refined over whole grains boosts your heart attack risk by up to 30 percent, so it's time to start shopping wisely. Here's a primer on refined grains and their effect on your heart.

Though shopping wisely isn't as easy as buying some brown bread or multi-grain cereal. These products can sometimes be impostors. Be sure to look at the label so you won't be fooled. Often, products that seem like they're made with unrefined grains are just the same refined products that raise the risk of high cholesterol, high blood pressure, heart attacks, insulin resistance, diabetes and abdominal fat.

Though, eating refined grains isn't just a 21st-century malady.

In ancient Egypt, rich people feasted on breads made from hand-sieved grain. In European manor houses, the kitchen staff filtered wheat flour through silken sieves to remove the gritty (nutrition rich) brown bits.

But that was then — here's what we know about refined and unrefined grains today.

Refined grains are commercially milled and polished these days — in fact, 27 kilograms (60 pounds) of wheat leaves the mill as almost 20 kilograms (45 pounds) of white flour.

Wheat bran — the brown, fibre-rich outer layer of the wheat grain, filled with niacin, thiamine, riboflavin, magnesium, phosphorus, iron and zinc.

Wheat germ — the grain's rich inner layer, that not only contains more of these nutrients, but also, vitamin E, some protein and fat.

Taken together, the bran and germ contain up to 90 percent of the grain's nutrients.

So what's the benefit of refining grain? Merely a longer shelf life.

At least seven major studies show that women and men who eat more whole grains (including dark bread, whole-grain cereals, brown rice, bran and other grains, such as bulgur and kasha) have 20 to 30 percent less heart disease.

Those who opt for refined grains have more heart attacks, insulin resistance and high blood pressure.

Refined grains have this effect because blood sugar levels climb higher and faster after you eat a slice of white bread or a scoop of white rice. Raising blood sugar levels raises insulin levels, which in turn decreases levels of high-density lipoproteins (HDLs) or "good" cholesterol and increases triglyceride levels.

Because of its effect on insulin levels, eating refined grains also raises your risk of insulin resistance and Type 2 diabetes.

If you opt for whole-grain bread or brown rice, the increase in blood sugar is not as high and is stretched over a longer period.

When nutritionists measured the waistlines of 459 people, they found that those who ate the most refined grains saw their midriffs expand by one centimetre (1⁄2 inch) a year. Abdominal fat releases heart-threatening hormones and fatty acids 24 hours a day. It also deprives arteries of a huge range of protective substances found in whole grains, including cholesterol-lowering soluble fibre and antioxidants.

Read the ingredient list on packaged grain products. At the top of the list should be whole wheat or another whole grain, such as oats, and the fibre content should be at least three grams (3/4 teaspoon) per serving.

And remember: Wheat bread is not necessarily whole wheat and neither is brown bread. And wheat flour does not mean whole wheat flour.

Keep all of this information in mind the next time you're in the grocery store to shop smarter and choose foods with healthier unrefined grains.