"The literature and science behind the link is very scattered, and I would say it hasn't been in the news enough, so a lot of people who treat mental illness aren't up to date," says Ruth Leyse-Wallace, who recently gave a talk on the topic at the National Alliance on Mental Illness' annual meeting in Seattle. "We need more nutritional assessments integrated into institutions."
When Leyse-Wallace performed assessments on admitted patients, she was often startled by the degree of serious malnutrition she encountered. "I can remember one lady that was in the general psychiatric unit," Leyse-Wallace says. "When I looked at her tongue, you could not believe the nutritional deficiencies in her mouth."
Leyse-Wallace - who notes that psychological symptoms of malnutrition always surface before physical symptoms, such as the lesions she discovered on her patient's tongue - firmly believes it's impossible to properly treat a patient without addressing his or her nutritional needs.
"It affects how their brain functions," Leyse-Wallace says of the various vitamin and mineral deficiencies that afflict patients for whom balanced meals might take a backseat to diagnosis management techniques such as therapeutic treatment or psychotropic drugs. "It affects their overall mental and physical health."
While inadequate nutrition can create setbacks in institutional settings, Leyse-Wallace says people coping with mental illness aren't the only people whose moods can suffer according to what they eat. Leyse-Wallace says many of the best studies linking mental health and dietary choices are applicable to the general population.
Research shows, for example, that people who don't get the Vitamin C they need are prone to suffer from depression and fatigue.
"Seven percent of Americans are deficient in Vitamin C," Leyse-Wallace says. "That's a lot of people."
According to Leyse-Wallace, many eaters fail to think about the emotional cost of cutting carbohydrates or other essential nutrients from their diets when they're trying to lose weight. She warns that the inability to focus, feeling tired and other common complaints could stem from rigid diets which starve the brain of the fuel it needs to perform cognitive tasks.
Linking Nutrition to Mental Health, Leyse-Wallace's 2008 book, compiled all the relevant studies of the subject she could find. But she suspects researchers who aren't explicitly concerned with the relationship between the mind and menus may be getting tripped up by not controlling for nutritional variables.
"You try to get populations equal, and I just don't believe you can if you don't know the nutrition is equal," she says.
At the Seattle event, Leyse-Wallace was approached by many attendees who wanted to know whether they were eating correctly in light of their mental conditions.
"I don't tell people what to eat because it should be individualized," she says. Still, she adds, "I don't personally see the advantage of taking $150 vitamins, and if a person is drinking 15 to 20 cups of coffee a day, that's not good."