Nutrition, a puzzle?

By Linda Falcon, nutritionnist

Last March, this question appeared on the colorful Nutrition Month poster. The image on the poster was a rubik's cube with each side of the cube representing an appealing meal. Eating well is not an easy task. To put all the pieces of the puzzle together requires time and effort. But too many people sacrifice eating well because they prioritize work. Also, obsession with body weight decreases the ability to make healthy choices.

What is eating well?

Eating well provides over fifty essential nutrients to insure physiological functions and psychological well-being. Nutrients have specific roles and are interdependant in their absorption and utilization by the body. Since no food contains all the required nutrients, eating a variety of food prevents deficiencies. The Canadian Food Guide was conceived to aid our choices toward food groups of different nutritional content. Regularly including a sufficient amount of food from each group guarantees an adequate nutrient intake. Not to forget! foods are first of all energy, fuel for the human machine in order to function properly. Energy balance and food variety are two fundamental elements of healthy eating.

What is energy balance?

Most of the energy coming from food consumption is used without so much as lifting a finger. In a resting and comfortably sitting or lying position, 60 to 70% of the energy is burned to maintain vital functions.

Vital functions are heart beating, respiratory work, kidney filtration and cells regeneration. This energy expenditure is basal metabolism. There is also energy used for digestion and for maintenance of body temperature and muscular tone.

But humans do not rest all the time. Academic, professional and discretionnary activities such as cleaning the house, socializing and regular exercising requires energy too. The energy expenditure depends of the type of regular activities. Energy balance is maintained when energy intake approximately equals energy expenditure. Recommended energy intake for a 19 to 49 years old woman weighing 58kg with a moderate level of activity is approximately 2200 kcal a day.

Where does the energy come from ?

Energy comes from carbohydrates, fats and to a lesser degree, from proteins. Carbohydrates are the main source of energy. More than half of the total energy intake comes from carbohydrates. In normal conditions, the nervous system and red blood cells use only energy from carbohydrates. Carbohydrates are divided into two distinct groups: complex carbohydrates which are the most available, such as starch, are found in bread and cereals. Simple carbohydrates are the sugars found in various foods such as fruits, vegetables, milk, and products like jam and honey.

Should fats be avoided ?

Fats are an essential part of the diet. 30% of daily energy intake comes from fats. They are sources of essential fatty acids which intervene in the regulation of blood pressure and in the hormones synthesis.

They are carriers for vitamins and are a constituent of cell membranes. Nutritional research has made us aware about our society's high consumption of fats and its negative effects on health. However, this information should be regarded in the proper perspective. In the process of learning healthy eating behaviors, health risks that constitute excessive fat intake should not be a concern. Diversified food sources of fats provide different types of fatty acids. For examples, vegetable oils, nuts, wheat germ and fish are sources of poly-unsaturated fatty acids; olive oil is a source of mono-unsaturated fatty acids; meat and dairy products are sources of saturated fatty acids.

When are proteins used for energy ?

Proteins are versatile. Amino acids resulting from their digestion are rearranged to build tissues, enzymes, hormones, red blood cells and antibodies. Others are used to maintain water, electrolytes and PH balance. But, if the diet is restricted in fats and carbohydrates, proteins are sacrificed. They are used as a source of energy rather than filling their primary role, and produce toxic waste in the body. Meat and alternates such as eggs, legumes, tofu and nuts are excellent sources of proteins. Dairy products are good sources of proteins.

Eating well, a source of satisfaction ?

Eating well means choosing foods that satisfy nutritional and physiological needs. But one should not underestimate the psychological well-being reached through appreciating a nice meal, choosing foods for their taste and through traditional rituals related to eating.

Inspire yourself from the 4 food groups of the Canadian Food Guide to plan your meals and feel good about it!

Breakfast:

1 bowl of cereals, milk and banana
1 toast with peanut butter and honey

Lunch:

Vegetable soup with a tuna sandwich
Vanilla yogurt with slices of cantaloupe

Dinner:

Spaghetti with tomato and lentil sauce, green salad with olive oi
A piece of cheese with grapes