Nutrition and Mental Ability

Important new research at Baycrest Centre for Geriatric Care clearly suggests a link between nutrition and cognitive decline with age. It’s been known for many years that deficiencies in several key nutrients was associated with lower levels of cognitive performance – including tests of memory — in otherwise healthy seniors, even if signs of malnutrition were not evident. These types of nutritional deficiencies are indicative of diets low in fruits and vegetables and high in cholesterol, monounsaturated and saturated fatty acids. (This is the same profile of poor nutrition that is associated with higher risk of disease, as discussed below.)

The key nutrients associated with cognitive performance are riboflavin (vitamin B₂), ascorbate (vitamin C), folate (folic acid) and Vitamin B_12. In addition, there are cognitive benefits associated with antioxidant intakes, in particular past (but not current) intake of Vitamin E. It’s important to recognise that seemingly adequate diets may not provide sufficient amounts of these nutrients. In fact, recommended levels of folic acid are currently under review with an eye toward increasing them. be aware that your current levels of nutrients might not be adequate and could contribute – if only in a small way – to cognitive decline.

Other factors
These proposed links between diet and cognitive function could be due to other factors, including smoking, alcohol consumption, and stress. For example, high levels of stress could lead to poor diet, high risk for cardio-vascular disease, and poor cognitive performance. Because research with humans makes it difficult to untangle these factors – scientists cannot and will not deliberately expose groups of people to stress in order to measure the impact on diet and memory – we must turn to studies using animals.

Drs. Carol Greenwood and Gordon Winocur of Baycrest Centre for Geriatric Care found that adult rats fed a diet high in fat for three months developed cognitive impairments. Conversely, studies of rats fed reduced calorie diets demonstrated reduced levels of cognitive decline.

If we look at the animal and human studies together, we see considerable evidence that poor diet is indeed a factor associated with cognitive decline – as well as other deficits, which we will see shortly.

While these studies have emphasised the long-term implications of poor diet, the immediate diet can also influence brain function. Water soluble vitamins, because they’re not stored in the body as readily as fat soluble vitamins, are especially important. So an important lesson to bear in mind is that good nutrition must be an on-going concern. A proper diet, with adequate amounts of key nutrients, is a good investment in your long-term well-being.

Scotiabank is committed to helping provide Canadians the tools they need to enjoy health and well-being as they age. We are proud to fund this innovative report. Congratulations to Baycrest on your vision and leadership.