Sugar and Fat
Are sugar and fat unhealthy? It depends on the source
Runners often wonder if sugar and fat are bad for them. There is an overwhelming amount of information online villainizing certain food groups (mainly these two), so it’s no wonder we get confused. Meals should be well balanced, with 20 to 30 per cent of total calories from protein, an equal amount from fat and at least 50 per cent from carbohydrate. They should also taste good and be enjoyable to make. When we restrict or eliminate specific macronutrients (i.e., carbs, protein or fat), we lose sight of this and potentially compromise our performance, health and enjoyment of life. On the other hand, some sources are more health-promoting than others.
Dietary fat
Healthy fats are a concentrated source of energy and are important for growth and development and for the absorption of fat-soluble vitamins, and should make up 20 to 30 per cent of calories. (They also add f lavour, consistency and stability to foods.)
Fats are either saturated (from all animal sources and some plant sources, such as coconut and palm oil) or unsaturated, which are considered healthier. Saturated fat should be limited to less than 10 per cent of daily calories, because of the link between saturated fat, blood cholesterol and heart disease. Healthy fats also include omega-3s (see sidebar for sources). Note: recent research has found that certain foods rich in saturated fats (wholefat dairy, dark chocolate and non-processed meats) are not associated with any increased risk of cardiovascular disease or diabetes, so if you consume saturated fat, it should be from these sources.
Trans fats are manufactured, and may be present in commercial baked goods and partially hydrogenated margarine. There is strong evidence to support avoiding them entirely (artificial trans fats are banned in Canada).
Carbohydrates – runners’ fuel
Carbohydrates are the main source of glucose/glycogen, which is the energy that fuels us. They include sugar, starch and fibre, and should comprise more than 50 per cent of a runner’s diet. They also promote optimal brain and muscle function and help regulate blood sugar levels.
Minimally processed carbohydrate foods also provide important vitamins and minerals (iron, calcium, vitamin C, folic acid, potassium, magnesium) and fibre.
Where do added sugars fit in?
Foods with natural sugars (see sidebar) have more healthy nutrients like fibre, vitamins and minerals, so they help keep you full and energized for longer. Most processed foods contain added sugars and many are low in nutrients and high in calories. Health Canada and other health organizations around the world recommend limiting foods and drinks that are high in added sugars.
Athletes need to derive more than 50 per cent of their energy from carbohydrate sources, and some of this will include added sugars, just to meet calorie needs. Since our carbohydrate needs are determined by the duration and intensity of exercise, if a person is only eating high-fibre carbohydrates, they may fall short on the higher training days. Sports drinks, gels, chews and other types of sports nutrition (which are primarily made of sugar) serve a purpose when the body runs out of stored carbohydrates (i.e., glycogen) during long and intense runs and races. In this scenario, they help meet that need to replenish fuel. But for recovery and day-to-day nutrition, aim to get most of your carbohydrates from whole foods.
Rachel Hannah, RD, is a five-time Canadian champion, a Canadian Marathon Championships silver medallist and a Pan Am Games bronze medallist in the marathon. She is a full-time registered dietitian at the University of Guelph’s Health and Performance Centre. She can be reached at rachelhannahrd@gmail.com.