Question: Leslie, first of all, what foods raise cholesterol? What are the worst culprits?

A steady intake of saturated and trans fats raise LDL cholesterol. Saturated fat is found in fatty cuts of meat, sausages, bacon, poultry with the skin, and high fat dairy products such as whole milk, cream, cheese and butter.

Trans fats are found in many commercial baked goods, snack foods, deep-fried foods and certain margarines. Worse, these fats also decrease HDL, or good, cholesterol.

So the first step in lowering your cholesterol is to limit your intake of these foods as much as possible.

Question: What are the foods used in this study to lower cholesterol? By how much?

This was a multi-center trial that enrolled 351 adults with elevated cholesterol. The group whose daily diets included foods rich in soluble fibre, nuts, soy protein and plant sterols lowered their LDL cholesterol by 13%. The group that followed only a low saturated fat diet reduced their blood cholesterol by only 3%.

Each of these foods has been show to lower blood cholesterol on its own. But when combined in your daily diet, this "portfolio" of foods has a much more dramatic effect.

Question: Walk us through each of these food groups. How much do you need each day?

Soluble fibre This type of fibre, plentiful in oats, oat bran, barley and psyllium, traps dietary cholesterol and fat in the digestive tract and speeds their removal from the body.

Good sources include oat bran, oats, barley, oat bran bread, psyllium-enriched breakfast cereals, Metamucil, and psyllium husk. Other good sources of viscous fibre include okra and eggplant.

The amount of viscous fibre participants ate in the study would be found in 2/3 cup of Kellogg's All Bran Buds, barely soup and a sandwich on oat bran bread and 2 teaspoons of Metamucil or 4 teaspoons of psyllium husk per day in a smoothie, juice or water.

Soy foods Foods like soy beans, soy nuts, firm tofu, soy burgers, soy hot dogs and soy beverages contain soy protein which helps lower blood cholesterol. The 2000-calorie diet in the study had 45 grams of soy protein. Two cups of soy milk, ¼ cup of roasted soy nuts and a soy burger or ¾ cup chopped tofu delivers a total of 45 grams of soy protein.

Nuts Studies have consistently found that nuts, packed with heart healthy unsaturated fat, help reduce blood cholesterol. You need to eat 1.5 servings per day. One serving is equivalent to 28 grams worth of nuts: 24 almonds, 18 cashews, 20 hazelnuts, 28 peanuts, 20 pecan halves, 49 pistachios and 14 walnut halves.

Plant sterols These natural compounds reduce the absorption of dietary cholesterol by 50 percent. Plant sterol-fortified foods such as margarine, yogurt, yogurt drinks and fruit juice are now available in grocery stores.

You need 2 grams of plant sterols per day. Five teaspoons of Becel pro-active margarine and President's Choice Blue Menu Celeb margarine have 2 grams of plant sterols. You can also get 2 grams of plant sterols in two 100 gram servings of Astro Biobest, two 80 ml servings of Danacol, two servings of President's Choice Blue Menu yogurt with plant sterols, or 2 cups of Oasis CholestPrevent juice.

For best results, consume plant sterol fortified foods two times per day rather than only once.

  • Question: So does this mean we can still eat all the cheese and butter we want – as long as we eat these foods?

No. I'm afraid not. If you have high blood cholesterol and your diet is high in saturated fat, reducing your intake will help to lower your cholesterol level. Participants were already following fairly healthy diets before they started the study. Had their diets been more reflective of the typical Canadian diet, blood cholesterol levels would have declined even further.

Additional key points about the study:

  • The researchers, led by Dr David Jenkins, from the University of Toronto, reported their findings in the Journal of the American Medical Association
  • The findings show that a diet combining soy protein, nuts and vegetable oils was found to lower "bad" cholesterol levels far more effectively than avoiding saturated fats
  • Over a six-month period, it resulted in a "meaningful" 13% reduction in blood levels of harmful low-density lipoprotein (LDL) cholesterol
  • The cholesterol-lowering diet also led to a predicted reduction in 10-year heart disease risk of almost 11%
  • A total of 351 patients from four Canadian centres took part in the study, all of whom suffered from high cholesterol.

The ‘portfolio' diet includes four types of foods recognized for their ability to lower cholesterol:

  • Soy protein. The portfolio diet calls for substituting soy-based meat products for meat, such as soy burgers, soy hot dogs, and soy cold cuts. Soy milk and soybeans are also good sources of soy protein.
  • Sticky fiber. The diet incorporates fiber from oats, barley, and psyllium.
  • Plant sterol esters. The diet replaces butter and margarine with plant sterol ester-enriched margarine.
  • Nuts. A handful a day of tree nuts, such as almonds or walnuts, and peanuts are included in the diet.