Oxford University Press's
Academic Insights for the Thinking World

Diet and age-related memory loss [excerpt]

Age-related memory loss is to be expected. But can it be mitigated?

There are many different steps we can take to help maintain and even improve our memories as we age. One of these steps is to make a few simple dietary changes. The following shortened excerpt from The Seven Steps to Managing Your Memory lists dietary basics that can benefit memory.

Omega- 3 fatty acids

Omega- 3 fatty acids (often shortened to “omega- 3s”) are impor­tant for a number of functions in the body, including the proper function of our brain cells and reduction of inflammation. Although our bodies make many of the fats we need, we cannot make omega- 3s, and so we need to get them from food. There are three main types of omega- 3s and, because you may have heard claims about each of them, we’ll mention them briefly (despite their long names). Docosahexaenoic acid (DHA) has been associated with brain health and cognitive function, con­trol of inflammation, as well as heart health. Eicosapentaenoic acid (EPA) has been associated with heart health and control of inflammation. Alpha- linoleic acid (ALA) is a source of energy and also a building block for both DHA and EPA. Scientific studies examining the benefits of omega- 3s have been mixed, but some research suggests that they may benefit brain health.

Our recommendation is to make sure your balanced diet does include some omega- 3 fatty acids. The most common sources of omega- 3s include fish (particularly fatty fishes such as salmon and tuna), walnuts, green leafy vegetables (such as kale), flaxseeds, and flaxseed oil. Other foods are now being fortified with omega- 3s. You may find eggs, milk, juice, and yogurt fortified with omega- 3s in your local grocery store.

The Mediterranean diet is low in saturated fats (the “bad” fats) but encourages the intake of monounsaturated “good” fats that lower the “bad” cholesterol. Credit: “olive-oil-salad-dressing-cooking” by stevepb. CC0 publi domain via Pixabay.

Vitamin D

Vitamin D is essential for brain health. In one study, individu­als with low levels of vitamin D were about twice as likely to develop dementia and Alzheimer’s disease compared to those whose levels were normal. Most older adults don’t have enough vitamin D. Although you can make vitamin D through your skin, to do so you would need to spend a lot of time outside without sunblock, which you shouldn’t do. We recommend a daily intake of 2,000 IU of vitamin D3, usually from supple­ment pills. You can also get vitamin D from fatty fish (such as tuna and salmon), portobello mushrooms grown under an ultraviolet light, and foods fortified with vitamin D including milk, cereal, and orange juice. Be sure to read the label to see if the product you buy is fortified or not. Lastly, there are some important interactions between vitamin D and some prescrip­tion medications, so you should speak with your doctor prior to taking vitamin D supplements.

Antioxidants

Antioxidants can defend the body against the harmful effects of free radicals— chemicals that can damage cells, including brain cells. Some of the most common antioxidants are vita­mins A, C, and E, along with flavonoids and beta- carotene. Most studies looking at the impact of antioxidant supplemen­tation through pills have offered little support that taking these antioxidant pills improves thinking and memory. In fact, tak­ing high doses of antioxidants in pill form can be problematic, with some studies showing that high intake of antioxidants is associated with an increased risk of cancer and death and can negatively interact with certain medications. Thus, although some clinicians would recommend taking antioxidant supple­ments, such as vitamin E, we do not.

The evidence suggests that eating antioxidant- rich foods, such as fruits and vegetables, can reduce the risk of chronic health conditions such as heart disease and stroke, which, in turn, can improve the health of the brain. Many research­ers now believe that it is the types and variety of antioxidant foods that people are consuming that matters most, rather than simply the total amount of antioxidants consumed. We therefore recommend eating fruits and vegetables as part of a balanced diet.

Mediterranean diet

One of the most important ideas that has emerged from the scientific literature is that it may not be any one dietary item that makes a difference in the health of our brains. Instead, it is likely that the complex combination of nutrients obtained through a balanced diet is best. The Mediterranean diet is one such balanced diet that has shown promise for brain health. This diet calls for high consumptions of fruit, whole grains (like bulgur, barley, and brown rice), beans, and vegetables at every meal. The diet is low in saturated fats (the “bad” fats) but encourages the intake of monounsaturated “good” fats that lower the “bad” cholesterol. These healthy fats, found in olive oil, avocados, and nuts, should be eaten frequently. Fish is rec­ommended at least twice a week. Low to moderate amounts of dairy products such as yogurt and cheese can be consumed daily or weekly. Red wine is also a staple of the Mediterranean diet. Red meat and sweets (such as candy, cookies, cake, and ice cream) should be consumed sparingly.

One way the Mediterranean diet helps the brain is by reducing risk factors for stroke such as high cholesterol and diabetes. One study showed that brain volumes were larger for those who followed the Mediterranean diet, equivalent to being five years younger! Other studies have shown that people who eat a Mediterranean diet have a lower risk of mild cognitive impairment and Alzheimer’s disease dementia compared to those who ate a more typical diet. Not all studies support the idea that the Mediterranean diet is good for cognition and reduced risk of memory loss, but many studies do, and none of the studies reported any side effects that would caution against adopting such a diet in an effort to keep the brain healthy. We therefore recommend a Mediterranean- type diet to everyone looking to modify their lifestyle in a way that benefits brain health.

Featured image credit: “food-avocado-healthy-fresh” by gutolordello. CC0 via Pixabay.

Recent Comments

There are currently no comments.