Foods and Nutrients That May Improve Memory
The Problem of Memory Loss
Memory loss is a worrying or even frightening situation, but it doesn't necessarily mean that a person is suffering from dementia or Alzheimer's disease. There are many causes of memory loss, including following a diet that lacks essential nutrients and eating harmful foods. One strategy that may boost memory is to eat a healthy diet containing specific foods and nutrients.
Anyone who has more than a very minor memory problem should visit a doctor. Eating nutritious food can often be a big help in dealing with a minor difficulty in remembering things, though in some cases it may not be the only treatment that's required. Getting regular physical and mental exercise as well as sufficient sleep and avoiding unhealthy habits such as smoking and excessive alcohol consumption can also be helpful for memory loss.
Vitamins B12 and B6, Folate, and Memory Loss
A vitamin B12 deficiency can interfere with nerve function and cause confusion and memory loss that resemble Alzheimer’s disease. A person with serious memory loss should be under the care of a doctor, but the doctor may discover that the solution to the patient’s problem is to take vitamin B12 supplements.
Older people (those over sixty years of age) are most likely to develop a low vitamin B12 level in their bodies. In order to be absorbed through the lining of the small intestine, vitamin B12 must first be separated from food. The stomach must be sufficiently acidic for this separation to happen. Older people may have low stomach acid, which hinders the extraction of the vitamin from food. Once the vitamin is removed from the food, it must bind with intrinsic factor, a substance made by the stomach lining, in order to be absorbed. Older people may not make enough intrinsic factor.
Inadequate vitamin B12 absorption can lead to other problems, such as anemia. If a person's diet contains insufficient amounts of vitamin B12, folate (or folic acid), and vitamin B6, a substance called homocysteine may build up in the body. Homocysteine has been shown to impair memory. It also raises the risk of a heart attack or stroke.
Vitamin B12 in Food and Supplements
In supplements, vitamin B12 is not attached to food and is therefore unaffected by insufficient stomach acid. If a large enough dose of vitamin B12 is taken, some can be absorbed even without intrinsic factor. A person shouldn't take massive doses of the vitamin without a doctor’s advice, however.
A doctor may choose to give vitamin B12 shots or may prescribe sublingual vitamin B12 tablets. These tablets are placed under the tongue. As the tablet dissolves, some of the vitamin can be absorbed through the lining of the mouth, bypassing the digestive tract.
Boosting the intake of vitamin B12 from the diet may also be helpful. Only foods from animals contains the vitamin. These foods include meats, fish, dairy products, and eggs. Vegans eat no food from animal sources. Lots of vegan foods are fortified with vitamin B12, however. These include many non-dairy milks, vegan meat substitutes, and fortified cereals. It's not a good idea to eat massive amounts of one type of food in order to obtain a particular nutrient, though. A diet needs to be balanced.
Bacteria are used to produce the vitamin B12 in supplements and fortified foods. Some of the bacteria living in our large intestine make vitamin B12, too, but it's unclear how much of this nutrient we absorb. Most vitamin absorption takes place in the small intestine.
Correcting a vitamin B12, vitamin B6, or folate deficiency may solve a memory problem. There is no evidence that supplements containing these vitamins improve memory in people who already have adequate levels of each nutrient, however.
Food Sources of Folate (Folic Acid) and Vitamin B6
Leafy green vegetables are a good source of folate, which is a member of the vitamin B family. Synthetic folate is sold as folic acid. All of the B vitamins dissolve in water. Foods containing the vitamins shouldn't be cooked by a method that involves a lot of water, such as boiling, since some of the nutrients will enter the water and be lost.
Vitamin B6 is present in a wide variety of foods. These include meat, beans, cereals, fruits such as bananas, avocados, and prunes (or dried plums), and vegetables such as potatoes and sweet potatoes that still have their skin.
Some Memory-Boosting Foods
Vitamin D Deficiency and Memory Problems
Vitamin D is very important for cognitive functions such as thinking, reasoning, and remembering. The vitamin is made by our skin when ultraviolet light strikes it. Due to the valid concern about getting cancer from the sun’s rays, however, many people are wearing sunscreen on sunny days and are therefore making an inadequate amount of vitamin D.
People living at higher latitudes may have a problem with obtaining vitamin D in winter. At this time of year sunlight is too weak to stimulate much vitamin D formation. In addition, older people and people who cover their skin due to religious beliefs often make an insufficient amount of the vitamin.
Vitamin D in Food and Supplements
Health experts are increasingly recommending that we take a vitamin D supplement. The vitamin seems to be very important in many body processes in addition to memory and is not present at high levels in most foods. One type of food that does contain significant quantities of the vitamin is oily fish. Salmon and sardines are examples of oily and healthy fish. Eggs yolks also contain vitamin D. The vitamin is added to dairy milk. Mushrooms contain a fungal form of the vitamin.
There are two types of vitamin D in food. Cholecalciferol or vitamin D3 is found in animals and is also made by the human skin. Ergosterol is made by fungi and is found in their cell membranes. It's changed into ergocalciferol, or vitamin D2, by ultraviolet light. This process happens naturally. In order to increase the level of vitamin D2 produced by fungi, however, supplement manufacturers irradiate the fungi.
Both vitamin D3 and Vitamin D2 can be used by the human body and both are found in supplements and fortified foods. Vitamin D3 seems to be more potent, though.
A Dietitian Talks About Food and Memory
Potential Problems With Vitamin Supplements
There are some important points to keep in mind when taking Vitamin D supplements. Vitamins are classified as either water soluble or fat soluble. Vitamin C and members of the vitamin B family are water soluble. If these nutrients become too concentrated inside the body, the excess vitamins are excreted in the urine. Vitamins A, D, E, and K are fat soluble. If these vitamins become too concentrated, excess amounts are stored in body fat and could be dangerous.
Another problem with supplementation is that vitamins don't act on their own in the body. They require the help of other nutrients These helper nutrients are often present in food but may be lacking in supplements.
For these reasons, taking megadoses of vitamins isn't recommended unless prescribed by a doctor to treat a diagnosed nutrient deficiency.
Phytochemicals or Phytonutrients for Memory
Benefits of Berries, Fruits, and Vegetables
Researchers are discovering that in addition to their other benefits, plants contain beneficial compounds called phytochemicals or phytonutrients. These chemicals aren't necessary to keep us alive but have important health benefits. Some phytochemicals seem to help memory.
There is evidence that blueberries are useful for boosting memory. The beneficial phytochemicals in the berries are believed to be their anthocyanins. Anthocyanins are red, purple, or blue pigments in plants. Other foods containing anthocyanins include berries, cherries, dark colored grapes, plums, red apples with skin, red cabbage, beets, and red onions. They may have different varieties of anthocyanins from blueberries, but they are still healthy foods.
Foods containing quercetin may also be beneficial for memory. Quercetin is found in onions, apples, blackcurrants, many berries, apples, broccoli, cherries, and dark grapes.
Anthocyanins and quercetin are members of the flavonoid family of plant chemicals, which seems to offer many benefits for humans. It's a good idea to eat flavonoids even if we don't have memory problems.
Nutritional terms can sometimes be confusing. Flavonoids are a family of chemicals made by plants. Anthocyanins and flavonols are smaller groups within the flavonoid family. Quercetin is a type of flavonol.
Research has shown that people who regularly eat cruciferous vegetables maintain their memory better as they age compared to people who don't eat the vegetables.
Cruciferous vegetables belong to the family known as the Brassicaceae. Familiar vegetables in this family include broccoli, cabbage, brussels sprouts, cauliflower, and kale. They contain folate, but cruciferous vegetables seem to be more beneficial for memory than other folate-containing vegetables.
Cruciferous vegetables are interesting plants. In addition to folate, they contain chemicals called glucosinolates. These may reduce the risk of some types of cancer. It's definitely worth incorporating the vegetables into a diet.
Several groups of researchers have found that the Mediterranean diet is linked to improved memory. The diet is rich in plant foods and low in dairy and red meat. Its main fat is olive oil.
Tumeric and Curcumin
Another nutrient that may be valuable for memory is curcumin, which is a chemical present in turmeric. This yellow spice is used in curry and likely deserves a regular place in the diet.
The brains of people with Alzheimer’s disease contain deposits called plaques. The plaques are made of a protein called beta-amyloid. Curcumin has been found to reduce the level of beta-amyloid in the brain and also to reduce inflammation. Curcumin is even more effective at reducing inflammation when used with vitamin D. It should be noted that research exploring how curcumin's abilities affect Alzheimer's disease is continuing, however. The situation is not completely clear.
The subject of curcumin and its potential health benefits is related to an important topic in nutrition science. Just because we eat a nutrient doesn't necessarily mean that it will get to where it's needed in the body. First, the nutrient must be absorbed through the lining of the small intestine into the bloodstream. Secondly, it must stay intact long enough to do its job, or the active product of its metabolism must stay intact. If these requirements aren't met, the nutrient won't help us. The term "bioavailability" refers to the amount of a nutrient that is able to have an effect in the body.
Curcumin on its own has low bioavailability. Eating turmeric or curcumin with a fat (preferably a healthy oil) increases the bioavailability of curcumin. This is true for fat soluble vitamins as well. Eating curcumin with black pepper or a substance called piperine in black pepper also increases its bioavailability. Some people find that black pepper irritates their stomach, however.
Omega-3 Fatty Acids and DHA
A high fat diet should be avoided, but including some fat in the diet is important. The fat that is eaten should include monounsaturated oils, such as extra virgin olive oil (unheated) and a type of polyunsaturated fat known as omega-3.
The specific omega-3 fat that has been shown to improve memory is called docosahexaenoic acid, or DHA. It’s found in oily fish such as sardines, wild salmon, and mackerel. DHA is an important nutrient for the developing brain in a fetus and also reduces inflammation in the body.
Plant foods don't contain DHA. They do contain other forms of omega-3 fatty acids, which can be converted into DHA. This conversion process doesn't seem to be very efficient, however. Luckily, algal supplements containing docosahexaenoic acid are now available. These could be helpful for vegans, vegetarians, or other people who don't want to eat fish.
Foods That May Harm Memory
A high fat diet and weight gain have been shown to impair memory, especially in post-menopausal women. Trans fats are thought to be especially harmful. High blood cholesterol and high blood pressure also damage memory and often accompany weight gain. Even without these additional health problems, gaining a significant amount of weight is detrimental to memory.
Excessive alcohol use also impairs memory. It interferes with short-term memories and prevents them from being converted into long-term ones. The effects of low to moderate red wine intake are less clear, however.
Non-Dietary Factors That May Improve Memory
Some non-dietary factors are known to improve memory. One of these is obtaining regular exercise, which has been shown to significantly reduce the risk of dementia and Alzheimer’s disease. Avoiding smoking is important, too, since smoking harms memory by decreasing blood flow and oxygen supply to the brain. Mental exercise may help our ability to remember. Research suggests that we need to challenge our brain, especially as we age. Learning new things and solving reasonably difficult puzzles are two ways to do this.
The Importance of a Healthy Lifestyle
Memory is a complex phenomenon and isn't completely understood. As the Mayo Clinic article cited in the reference section below states, memory does tend to worsen as we age. We shouldn't assume that this situation is natural and ignore it, however. If our ability to remember worsens despite the fact that we're eating foods shown to boost memory and following a healthy lifestyle, it's time to visit a doctor. A healthy lifestyle is still worthwhile, though. It has many health benefits beyond the possible correction of memory problems.
There are probably many undiscovered factors that affect our ability to remember things. At the moment, the best steps to improve or preserve memory seem to be eat a healthy diet, exercise regularly, get enough good-quality sleep, exercise the brain, seek a doctor's advice when necessary, and avoid foods and habits known to cause memory loss. Making sure that we eat nutrients that may improve our memory, including the ones mentioned in this article, also seems like a good idea.
- Symptoms of a vitamin B12 or folate deficiency from the NHS (National Health Service)
- University of Kentucky. (2013, December 2). New study suggests low vitamin D causes damage to brain. ScienceDaily. Retrieved July 28, 2017 from www.sciencedaily.com/releases/2013/12/131202121101.htm
- Effects of blueberries and strawberries on cognitive decline from the NIH (National Institutes of Health)
- Effects of cruciferous vegetables on cognitive decline in women from the NIH
- Curcumin, Alzheimer's disease, and bioavailability from UCLA (University of California, Los Angeles)
- University of Alberta Faculty of Medicine & Dentistry. (2012, June 28). Why does a diet high in DHA improve memory?. ScienceDaily. Retrieved July 28, 2017 from www.sciencedaily.com/releases/2012/06/120628174534.htm
- Trans fats and memory from UC San Diego Health
- Strategies to help prevent age-related memory loss from WebMD
- The Mayo Clinic has a useful article about deciding when to seek medical help for memory loss.
Questions & Answers
© 2010 Linda Crampton