Although we use our brains 24/7 how many of us think about what we should eat get most out of them? 

If you want to maintain your brain at its proper size and best function, eat a diet high in nutrients. That means plenty of veggies and not many cookies.

If you are an older person who wants to maintain your brain, you should be very careful about what you eat. 

You may feel that lifestyle changes after age 65 couldn’t make much difference for your health. On the contrary, a healthy diet continues to be critical. If not more so.

A Whole-Food Diet is best to Maintain Your Brain

A study1 of more than 4,000 Dutch people with an average age of 66 found that those eating more vegetables, fruit, fish, and nuts had bigger brains than those who ate processed meat and drank sugary beverages.

The volunteers filled out detailed dietary questionnaires and then went through MRI brain imaging. The investigators then calculated diet quality scores for all the participants. 

In addition, they adjusted for other factors known to affect brain size, including age, sex, smoking, and physical activity. 

The scientists found, after the adjustments that people who ate healthier food had bigger brains. The difference came to about two milliliters on average. A typical person experiences about 3.6 milliliters of brain shrinkage in a year. No single food accounted for this difference; it appears to be linked to overall diet quality.

The researchers concluded:

“High intake of vegetables, fruit, whole grains, nuts, dairy, and fish and low intake of sugar-containing beverages were associated with larger brain volumes.”

Diet Also Affects Brain Power

The size of the brain is not all that may be affected by diet. Previous research linked a whole-food diet rich in vegetables to better brain function as well.

The Journal of Alzheimer’s Disease tracked dietary data of more than 900 senior citizens over the course of a year.2 Neuropsychologists, nurses, and doctors then evaluated their mental function. Only those who were free of any signs of dementia or cognitive decline were followed over the next few years.

It was found that older people who consumed the most bread, pasta, cereal, cookies, and other carbohydrates had a substantially higher risk of cognitive decline than those who ate the fewest carbs. 

Conversely, high-fat diets were linked to less trouble with memory, judgment, and language. 

Higher protein diets were also associated with a slightly reduced risk. 

The authors suggest that the more carbs people consume, the greater the likelihood that high blood sugar and insulin levels might interfere with brain function. 

They concluded:

“A dietary pattern with relatively high caloric intake from carbohydrates and low caloric intake from fat and proteins may increase the risk of MCI [mild cognitive impairment] or dementia in elderly persons.”

A Mediterranean Diet Could Help Maintain Your Brain

The Mediterranean diet appears to protect people against heart disease. In addition, it may also protect the brain from Alzheimer’s disease. One study tested more than 1,800 elderly New Yorkers every few years between 1992 and 2006.3

The scientists analyzed the volunteers’ exercise and dietary habits. The findings found that those who were most physically active and most closely followed a Mediterranean-type diet were significantly less likely to be diagnosed with Alzheimer’s disease.

The same issue featured a five-year French study of 1,410 older people living in Bordeaux4. Participants eating a Mediterranean diet performed better on a test of mental function. These individuals were following the French version of a Mediterranean diet, rich in vegetables, fruits, and beans. Olive oil is the main source of fat, although nuts are also an important component. This appears to be a tasty way to improve the chance of enjoying a healthy old age.


  1. Croll et al, Neurology, online May 16, 2018. 
  2. Roberts et al, Journal of Alzheimer’s Disease, Oct. 2012.
  3. Scarmeas et al, Journal of the American Medical Association, August 12, 2009
  4. Féart et al, Journal of the American Medical Association, Aug. 12, 2009