Canada’s Food Guide has been setting serving size recommendations for decades and as it celebrates its 70th anniversary, a new study shows that we still are not clear on how much to eat.
The first guide was called Canada Food Rules and launched in July 1942 as a tool to help prevent nutritional deficiencies amidst wartime.
But researchers say 70 years after it was introduced, Canadians are living in an era of supersized meals and have trouble relating to the guide’s handling of serving sizes.
York University researchers found that participants in a study published online Wednesday in the journal Applied Physiology, Nutrition and Metabolism commonly overestimate the size of one serving of food as defined in Canada’s Food Guide.
In fact, the majority of study participants inaccurately thought they would need to increase their food consumption by approximately 400 calories to meet the recommendations.
“If they did that, they would be overeating,” said lead author and dietician Sharona Abramovitch.
She analyzed food records from the 145 participants in the study, which included white, black, south Asian and east Asian adults.
All four groups inaccurately estimated the total number of servings they were eating in a day: They underestimated the number of servings of fruit and vegetables, grain products and meat and overestimated the number of servings of milk and alternatives they were eating.
“People are confused with servings and portion terminology. In some languages, serving and portion mean the same thing,” said Abramovitch.
“People commonly thought a serving was the amount of food on their plate.”
The guide measures servings in millilitres, cups, grams and ounces. For example, one serving of fruit or vegetables could be one cup of salad, half a cup of vegetables or half a cup of 100 per cent juice, which can get confusing. For others the measurements were meaningless, said Abramovitch.
“Some ethnic groups don’t use cups in cooking and couldn’t relate to that measurement,” said Abramovitch.
“We really haven’t found the best way of illustrating how much food people should be eating.”
Dietitian Leslie Beck agreed and said that we have not done a good job teaching healthy portion sizes in Canada.
“We barely cover the food guide in schools,” she said
“Serving size information is really important because it relates to calories. Understanding our food intake needs are vital when 60 per cent of Canadian adults and 26 per cent of kids are obese.
Living in an era of supersized meals complicates things further.
It is not uncommon for steaks served at a typical Canadian summer barbecue to exceed a person’s daily allowance for meat.
“It’s hard to know what a serving size is when big sizes are the norm,” Beck said.
“Serving sizes in restaurants, grocery stores and in the home have grown over the last 30 years. We tend to think a serving size is the amount of food in front of us, regardless of how much food is on our plate.”
She said it is difficult for governments to give clear cut messages on how much to eat because appropriate calorie intake and portion size depends of a number of personal factors.
“Canadians are aware of the guide, they know about the food groups. But figuring out how much to eat is the tricky part because it is personal and it depends on several factors such as weight, age, level of physical activity and gender,” Beck said.
There is a great deal of information on Health Canada’s website that allows people to look up their estimated calorie requirements and how much they should be eating from each food group.
However it does require people to be proactive, to be able to search though a number of different web pages and understand the language or source a translation in a language they do understand.
For example, a woman aged 31-50 who does moderate physical activity every day needs about 2,000 calories. That woman should have 7-8 servings of fruit and vegetables, 6-7 servings of grain products, two servings of milk and milk alternatives and two servings of meat and alternatives.
Then you have to determine how big a serving is. One serving of meat and alternatives for example is just 75 g or half a cup of cooked meat of fish or 175 ml of cooked beans.
The U.S. has moved away from servings with their recent MyPlate initiative, which depicts a plate separated into different groups, with vegetables taking up the largest amount of space.
Canada’s Food Guide was last updated in February 2007. With so many Canadians battling weight issues, critics said they wanted to see more of a focus on calories in the food guide and a greater sense of the link between overeating and disease.