There is no quick fix for the worldwide problem of obesity, but there are many useful tactics to fight it, researchers say.
"People want to find the one solution that will solve the problem, but there is no silver bullet," said Mike Mulvey, a consumer behaviour expert and marketing professor at the University of Ottawa.
A study published this week in the medical journal The Lancet argues that today's food environments exploit people's biological, psychological, social and economic vulnerabilities, making it easier for them to eat unhealthy foods.
This reinforces demand for foods of poor nutritional quality, furthering the cycle of unhealthy food environments. In order to tackle the obesity epidemic, regulatory controls and education campaigns need to be reconsidered, food experts say. That echoes a main recommendation of the study.
While our psychological and biological taste buds are drawn to junk foods that contain high levels of fat, sugar and salt — which food industry giants make even harder to resist with concepts such as "bliss point" (food manufactured to bring the most pleasure possible), "mouth feel" (enjoyable fat compounds) and "flavour burst" (added salt) — it's not just the manipulation of taste that makes junk food so attractive.
It's the convenience, dietitians say. People just love convenience.
"Even lawyers run down to the food court for what's convenient," said Leah Shainhouse, a private practice dietitian.
Shainhouse and fellow dietitian Abby Langer agree that people are aware of what's healthy and what's not, but many people don't cook for themselves and their families because they're too busy.
"People are trapped in habits related to food and convenience," said Mulvey. "What they need to do is large scale."
Mulvey said the nutritional claims for food products need to be more transparent.
According to the book Salt Sugar Fat: How the Food Giants Hooked Us by Michael Moss, large food manufacturers will call a product low-fat while boosting its sugar and salt content.
"In the back of people's minds they do know what you eat is important, but they are not aware of exactly what they're putting in their bodies," said Shainhouse.
Controlling portion sizes and enforcing transparent marketing are popular options for government regulation, but people working in the field emphasize nutrition education.
If nutritional information on food labels is unclear or it isn't available in restaurants, people will assume that because they are eating healthy, they don't need to pay attention to portion size, said Shainhouse.
"Have nuts for a healthy snack, yes, but how many of those nuts are you eating? Determine portion sizes before you dive in."
Regulating gigantic soft drink sizes has been somewhat successful.
"When you look at the soft drink giants, I don't think it's any secret that they are hurting," said Sylvain Charlebois, a University of Guelph professor of food distribution and policy.
"There's evidence out there that the modern consumer is looking for healthier products. Coke is going into milk production. Is there another more wholesome food than milk?"
Some regulatory measures resonate with food experts.
One suggestion from the study in The Lancet is to tax "health-related" foods less than junk foods, but food experts don't agree regulation is the best suggestion.
"Prices will affect consumption, but it could have different effects at different income levels," said Mulvey. "Alcohol and tobacco are taxed to death and Canadians are still heavy users, because it's fun. Food is fun, too. It's not just functional."
Abbey Langer, a consulting dietitian and a council member of the College of Dietitians of Ontario, said, "You have to be careful what you regulate, because you don't know the wider impact of it."
People who eat fast food because their income is limited won't necessarily change their habits if junk food becomes more expensive. Instead, they might eat even lower quality food.
"It won't change larger habits or encourage people to exercise," Langer said.
Nutrition education for kids and adults
Educating people is a more popular approach. Nutrition is not part of a North American education the way it is in countries such as Japan that have lower obesity rates.
Shainhouse tries to teach adults about healthy eating. She is using Nutrition Month in March to bring workplace wellness to the business world.
"We are focusing on 9-to-5," she said. "I will do a presentation on what a healthy diet actually looks like, what a meal should consist of and find out what people are putting into their meals."
Educating people about marketing tricks is an important solution, said Mulvey.
"Some of the things we see marketers do are things like vending machines," he said. "Why would I go find something healthy when there are snacks right down the hall?"
Langer said, "It should be mandatory for kids to have nutrition in their school. In Japan it's mandatory and it's amazing. They learn how to cook and how to eat at a very early age. It has an impact on how people eat through their lives."
Children need to learn basic food literacy skills such as where food comes from and how to cook simple, healthy meals, said dietitian Christy Brissette.
"The best way for children to learn healthy eating habits is from their parents," she said. "As often as possible, parents should encourage children and teens to eat meals together as a family."
In France, school lunches are commonly provided to school children and contain fresh meat, vegetables and fish.
"French parents believe it is as important to teach your children to eat as it is to teach them to read," said Karen Le Billon, author of French Kids Eat Everything. "They view food as a fun family adventure; new tastes are something to be discovered together."