Eating a healthier diet, like the one recommended by the U.S. government, is no easy undertaking — not least because of its high cost. A new study published on Thursday in the journal Health Affairs calculates that it would cost the average American an extra $380 in fruits and vegetables per year to meet the government’s recommendation for potassium intake alone.
Healthy foods are expensive. Conversely, the unhealthier your diet gets, the less it costs. The study found that for each 1% increase in calories from saturated fat, food costs decline by 28¢; for each 1% increase in calories from added sugar, the savings equal 7¢.
“Nutrients actually cost money, and one reason people of limited means select foods with poor nutrition is because they are forced to,” says senior author Adam Drewnowski, director of nutritional sciences and a professor of epidemiology at the School of Public Health at the University of Washington. “When the dietary recommendations came out, they told us to eat fish, they told us to eat fresh fruits and vegetables, but there wasn’t really anything about cost. And in the current economic climate, we really should be talking about that.”
Not only are fresh, whole foods costly, but there isn’t enough of them to go around. Regarding the U.S. food supply, the researchers wrote:
The current system has proved to be remarkably effective in the provision of calories, but not as good at supplying nutrients. More fundamentally, the system currently falls short of producing enough vegetables and fruit to supply Americans with even the minimum recommended number of daily servings of these foods.
Based on data from the Seattle Obesity Study, in which a regionally representative sample of 1,123 adults filled out a survey about their food-consumption patterns, expenses and caloric intake, Drewnowski and his team calculated what it would cost for people to improve their diets to meet government guidelines.
Specifically, the researchers looked at the cost of boosting the four main nutrients that are most lacking in the average American diet: dietary fiber, potassium, calcium and vitamin D. To determine food prices, researchers averaged costs from three large conventional grocery chains: Albertsons, Safeway and Quality Food Centers.
Potassium was, calorie for calorie, the most expensive nutrient. U.S. guidelines recommend that Americans get 4,700 mg of potassium each day, but study participants got just 2,800 mg per day on average. In order to make up the difference, a person would have to spend an additional $1.04 per day, the researchers found. Getting enough dietary fiber and vitamin D would cost an additional 35¢ per nutrient per day. Calcium was plentiful enough in most diets, and from cheap enough sources, that it didn’t really affect cost, the study concluded.
Not surprisingly, people who spent the most on food had the most nutrient-rich diets and those lowest in saturated fat and added sugar. The researchers say that food cost is likely a major contributing factor to many people’s dietary choices.
So if the solution isn’t to eat less healthful foods, what can consumers do to improve their diet without going broke?
1. Get the most bang for your buck “Based on our data on food prices and nutrient composition, consumers could get potassium from bananas more cheaply than from nectarines, even though nectarines contain more potassium per calorie than bananas do,” wrote the researchers. Bananas are cheap, and each one provides 450 mg to 500 mg of potassium.
2. Choose “double duty” items Bananas contain potassium, but they’re also rich in dietary fiber — another nutrient most Americans don’t get enough of. Likewise, beans are a cheap source of dietary fiber, and many varieties, such as white beans, are also good sources of calcium.
3. Try dried or preserved fruits These fruits can be cheaper, have a longer shelf life and even be more dense in nutrients than the fresh versions. For example, dried prunes are a great, cheap source of dietary potassium, but they typically fly under consumers’ radar. One pitfall of eating dried fruits is that they’re high in sugar, so it’s best to be moderate.
4. Diversify As with all dietary matters, it’s a balancing act between getting enough nutrients while keeping calories down. Potatoes are a cheap source of potassium, for example, but you would need to consume an unreasonable 11 servings per day to get the recommended amount of the nutrient. A solution? For each serving of potatoes in your diet, add one serving of bananas, milk, seeds and nuts. You might not get the full 4,700 mg of potassium, but you’ll be moving in the right direction.