What you need to know about choline

Although your body makes some, you need to get choline from your diet to avoid a deficiency.

However, less than 10% of the US population seems to be getting enough of this nutrient.

Here is everything you need to know about choline, including what it is and why you need it.

What Is Choline?

Choline is an essential nutrient.

This means it’s required for normal bodily function and human health. Although small amounts of it can be made in the liver, the majority must be obtained from the diet.

Choline is an organic, water-soluble compound. It is classified as neither a vitamin nor a mineral.

However, it is often grouped with the vitamin B complex due to its similar properties and functions. In fact, this nutrient affects a number of vital bodily functions.

These include liver function, healthy brain development, muscle movement, the nervous system and metabolism, among others.

Therefore, adequate amounts are needed for optimal health and to reduce the risk of certain diseases.

Bottom Line: Choline is an essential nutrient that must be included in the diet to maintain optimal human health.

Choline Serves Many Functions in the Body

Choline plays an important part in many processes throughout the body.

These include the following key functions:

• Cell structure: It is needed to make fats that support the structural integrity of cell membranes.
• Cell messaging: It is involved in the production of compounds that act as cell messengers.
• Fat transport and metabolism: It is essential for making a substance required for transporting cholesterol from the liver. Inadequate choline may result in fat and cholesterol accumulating in the liver.
• DNA synthesis: Choline and other vitamins such as B12 and folate help with a process that’s important for DNA synthesis.
• A healthy nervous system: This nutrient is required to make acetylcholine, an important neurotransmitter. It’s involved in memory, muscle movement, regulating heartbeat and many other basic functions.

Bottom Line: Choline is involved in many different processes. These include cell structure and messaging, fat transport and metabolism, DNA synthesis and the nervous system.

How Much Do You Need?

In order to get enough choline, you need to obtain it from your diet. Yet due to a lack of available evidence, a Reference Daily Intake (RDI) value has not been set.

However, the Institute of Medicine has set a value for adequate intake (AI).

This value is intended to be sufficient for most healthy people, helping them avoid negative consequences of deficiency such as liver damage.

Nevertheless, requirements differ according to genetic makeup and gender.

In addition, determining how much choline a person consumes is difficult due to limited knowledge about the amounts present in different foods.

Here are the recommended AI values of choline for different groups:

• 0–6 months: 125 mg per day.
• 7–12 months: 150 mg per day.
• 1–3 years: 200 mg per day.
• 4–8 years: 250 mg per day.
• 9–13 years: 375 mg per day.
• 14–18 years, female: 400 mg per day.
• 14–19 years, male: 550 mg per day.
• Adult women: 425 mg per day.
• Adult men: 550 mg per day.
• Breastfeeding women: 550 mg per day.
• Pregnant women: 450 mg per day.

It is important to note that many people do fine with less choline, while others need even more.

In one study of 26 men, six developed symptoms of choline deficiency even when consuming the AI amount.

Bottom Line: The adequate intake of choline is 425 mg per day for women and 550 mg per day for men. However, requirements vary by individual.

Choline Deficiency Is Unhealthy, But Rare

Choline deficiency can cause harm, especially for the liver.

One small study of 57 adults examined the effects of a choline-deficient diet.

It found that 77% of men, 80% of Postmenopausal women and 44% of premenopausal women experienced liver and/or muscle damage after following the diet.

Another study found that when postmenopausal women consumed a diet deficient in choline, 73% developed liver or muscle damage.

However, these symptoms disappeared once they began getting enough choline.

Choline is especially important during pregnancy, as a low intake may raise the risk of neural tube defects in unborn babies.

One study found that a higher dietary intake around the time of conception was associated with a lower risk of neural tube defects.

In addition, low choline intake may raise the risk of other pregnancy complications. These include preeclampsia, premature birth and low birth weight.

Additionally, it should be noted that although most Americans do not consume adequate amounts in their diets, actual deficiency is rare.

Bottom Line: Choline deficiency is associated with liver and/or muscle damage. Low intake during pregnancy is linked to complications.

Some People Are at Risk of Deficiency

Although choline deficiency is rare, certain people are at an increased risk:

• Endurance athletes: Levels fall during long endurance exercises, such as marathons. It’s unclear if taking supplements improves performance.
• High alcohol intake: Alcohol can increase requirements and the risk of deficiency, especially when intake is low.
• Postmenopausal women: The hormone estrogen helps produce choline in the body. Since estrogen levels tend to drop in postmenopausal women, they may be at greater risk of deficiency.
• Pregnant women: Requirements increase during pregnancy. This is most likely due to the unborn baby requiring choline for development.

Bottom Line: People who are at an increased risk of deficiency include athletes, those who drink a lot of alcohol, postmenopausal women and pregnant women.

Top Dietary Sources of Choline

Choline can be obtained from a variety of foods and supplements.

Food Sources

Dietary sources are generally in the form of phosphatidylcholine from lecithin, a type of fat.

The richest dietary sources of choline include liver, eggs, fish, soybeans, cauliflower and broccoli:

• Beef liver: 1 slice (2.4 oz or 68 grams) contains 290 mg.
• Chicken liver: 1 slice (2.4 oz or 68 grams) contains 222 mg.
• Eggs: 1 large hard-boiled egg contains 113 mg.
• Fresh cod: 3 oz (85 grams) contain 248 mg.
• Salmon: A 3.9-oz (110-gram) fillet contains 62.7 mg.
• Cauliflower: 1 half cup (118 ml) contains 24.2 mg.
• Broccoli: 1 half cup (118 ml) contains 31.3 mg.
• Soybean oil: 1 tablespoon (15 ml) contains 47.3 mg.

So a single egg supplies about 20–25% of your daily requirement, and two large eggs provide almost half of your daily requirement.

In addition, a single 3 oz (85 grams) serving of beef kidney or liver can supply all of a woman’s daily requirement and most of a man’s.

Bottom Line: Rich food sources include beef liver, eggs, fish, nuts and certain vegetables like cauliflower and broccoli.

Additives and Supplements

Soy lecithin is a widely used food additive that contains choline. Therefore, it is likely that some extra is consumed through the diet via food additives.

Lecithin can also be purchased as a supplement. However, lecithin tends to only contain 10–20% phosphatidylcholine.

Phosphatidylcholine can also be taken as a pill or powder supplement, yet choline comprises only about 13% of the weight of phosphatidylcholine.

Other forms of supplements include choline chloride, CDP-choline, alpha-GPC and betaine.

If you are looking for a supplement, CDP-choline and alpha-GPC tend to be higher in choline content per unit weight. They are also more easily absorbed than others.

Some sources claim that choline in nutritional supplements may reduce body fat, but there is little to no evidence to support these claims.

Bottom Line: Choline can also be taken as a supplement. CDP-choline and alpha-GPC seem to be the best types.

Choline and Heart Health

Higher intakes of choline have been associated with a reduced risk of heart disease.

Folate and choline are involved in the conversion of the amino acid homocysteine to methionine.

Therefore, a deficiency of either nutrient can result in an accumulation of homocysteine in the blood.

Elevated levels of homocysteine in the blood are associated with an increased risk of heart disease and strokes.

However, the evidence on this topic is mixed.

Although choline may lower homocysteine levels, the association of choline intake with heart disease risk is not clear.

Bottom Line: Choline may help reduce the risk of heart disease by lowering homocysteine levels. However, the evidence is mixed.

Choline and the Brain

Choline is required to produce acetylcholine, a neurotransmitter that plays an important role in regulating memory, mood and intelligence.

It’s also needed for the process that synthesizes DNA, which is important for brain function and development.

Therefore, it’s not surprising that choline intake has been associated with improvements in brain function.

Memory and Brain Function

Large observational studies link choline intake and blood levels to improved brain function, including better memory and processing.

Supplementing with 1,000 mg per day led to improved short- and long-term memory in adults aged 50–85 who had poor memory.

In a 6-month study, giving phosphatidylcholine to people with early Alzheimer’s disease modestly improved memory in one small subgroup.

However, other studies on healthy people and those with dementia found no effects on memory.

Bottom Line: A higher choline intake has been associated with improved memory function in some studies, but the evidence is mixed.

Brain Development

Several animal studies suggest that taking choline supplements during pregnancy may improve fetal brain development.

However, there are only a few studies on this in humans.

One observational study of 1,210 pregnant women found choline intake had no links to mental performance in the children at age 3.

Nevertheless, the same study found that a higher intake during the second trimester was associated with better visual memory scores in the same children at age 7.

Another study gave 99 pregnant women 750 mg of choline per day from when they were 18 weeks pregnant to three months after pregnancy. They found no benefits for brain function or memory.

Bottom Line: Animal studies show choline supplements during pregnancy can improve brain development. However, the evidence in humans is limited.

Mental Health

Some evidence suggests choline may play a role in the development and treatment of certain mental health disorders.

One large observational study found that lower blood levels were associated with a higher risk of anxiety, but not depression.

These levels are also used as an indicator for certain mood disorders, and choline supplements are sometimes used to treat bipolar disorder (48).

One study found that choline therapy improved symptoms of mania in individuals diagnosed with bipolar disorder

However, there are currently not many studies available on this.

Bottom Line: Choline may play a role in the treatment of disorders such as anxiety and bipolar disorder. However, more research is needed.

Other Health Benefits of Choline

Choline levels have been associated with the development and treatment of certain diseases.

However, for most of these, the relationship is not clear and research is ongoing.

Liver Disease

Although choline deficiency results in liver disease, it’s not clear whether intakes lower than the recommended levels lead to an increased risk of liver disease.

A study of more than 56,000 people found that normal-weight women with the highest intakes had a 28% lower risk of liver disease, compared to those with the lowest intakes.

The study found no association with liver disease in overweight women or men (51).

Another study of 664 people with non-alcoholic liver disease found that lower intakes were associated with greater disease severity.

Bottom Line: Limited evidence indicates that higher intakes of choline may reduce the risk or severity of liver disease in certain people.

Cancer

Some research has found that women with diets high in choline may have a lower risk of breast cancer.

One study involving 1,508 women found that those consuming diets high in free choline were 24% less likely to get breast cancer.

However, the evidence is mixed.

Other studies found no association with cancer, but lab studies have found that a deficiency may increase the risk of liver cancer.

Conversely, higher intakes have also been associated with an increased risk of prostate cancer in men and an increased risk of colon cancer in women (59, 60).

Bottom Line: The relationship between choline intake and cancer is not clear. In some cases, a higher intake may reduce the risk. For other cancers, a higher intake may increase the risk.

Neural Tube Defects

Higher intakes of choline during pregnancy may reduce the risk of neural tube defects in babies.

One study found that women who had higher intakes around conception had a 51% lower risk of neural tube defects, compared to women with very low intakes (61).

Another observational study found that pregnant women with the lowest intakes were more than twice as likely to have babies with neural tube defects (62).

However, other studies found no link between the mother’s intake and the risk of neural tube defects.

Bottom Line: Some evidence suggests higher choline intake during pregnancy may reduce the risk of neural tube defects.

Too Much Can Be Harmful

Consuming too much choline has been associated with unpleasant and potentially harmful side effects.

These include drops in blood pressure, sweating, fishy body odor, diarrhea, nausea and vomiting.

The daily upper limit for adults is 3,500 mg per day. This is the highest level of intake that is unlikely to cause harm.

It is very unlikely that someone could ingest this amount from food alone. It would be almost impossible to reach this level without taking supplements in large doses.

Bottom Line: Consuming too much choline has been linked to unpleasant and potentially harmful side effects.

Are Artificial Sweeteners Good or Bad.

Artificial sweeteners are often the cause of heated debate.

On one hand, they’re claimed to increase the risk of cancer and negatively affect your blood sugar and gut health.

On the other hand, most health authorities consider them safe and many people use them to eat less sugar and lose weight.

This article reviews the evidence on artificial sweeteners and their health effects

What Are Artificial Sweeteners?

Artificial sweeteners, or sugar substitutes, are chemicals added to some foods and beverages to make them taste sweet.

People often refer to them as “intense sweeteners” because they provide a taste that is similar to table sugar but up to several thousand times sweeter.

Although some sweeteners contain calories, the amount needed to sweeten products is so small that you end up consuming almost no calories.

Bottom Line: Artificial sweeteners are chemicals used to sweeten foods and beverages. They provide virtually zero calories.

How Do Artificial Sweeteners Work?

The surface of your tongue is covered by many taste buds. Each taste bud contains several taste receptors that detect different flavors.

When you eat, the different food molecules contact your taste receptors.

A perfect fit between a molecule and a receptor sends a signal to your brain, allowing you to identifying the taste.

For example, the sugar molecule fits perfectly into the taste receptor for sweetness, like a lock and key, allowing your brain to identify the sweet taste.

The molecules of artificial sweeteners are similar enough to sugar molecules that they fit on the sweetness receptor.

However, they are generally too different from sugar for your body to break them down into calories. This is why they have a sweet taste without the added calories.

Only a minority of artificial sweeteners have a structure that your body can break down into calories. Because only very small amounts of artificial sweeteners are needed to make foods taste sweet, you consume virtually no calories.

Bottom Line: Artificial sweeteners taste sweet because they are recognized by the sweetness receptors on your tongue. They provide virtually zero calories because most cannot be broken down by your body.

What Are the Names of Artificial Sweeteners?

These artificial sweeteners are authorized for use in the US and/or within the European Union:

• Aspartame: 200 times sweeter than table sugar. Aspartame is known under the brand names Nutrasweet, Equal or Sugar Twin.
• Acesulfame potassium: 200 times sweeter than table sugar. Acesulphame potassium is suited for cooking and baking and known under brand names Sunnet or Sweet One.
• Advantame: 20,000 times sweeter than table sugar, suited for cooking and baking.
• Aspartame-acesulfame salt: 350 times sweeter than table sugar, and known under the brand name Twinsweet.
• Cyclamate: 50 times sweeter than table sugar. Cyclamate is suited for cooking and baking. However, it’s been banned in the US since 1970.
• Neotame: 13,000 times sweeter than table sugar. Neotame is suited for cooking and baking and known under the brand name Newtame.
• Neohesperidin: 340 times sweeter than table sugar. It is suited for cooking, baking and mixing with acidic foods. It is not approved for use in the US.
• Saccharin: 700 times sweeter than table sugar. It’s known under the brand names Sweet’N Low, Sweet Twin or Necta Sweet.
• Sucralose: 600 times sweeter table sugar.Sucralose is suited for cooking, baking and mixing with acidic foods. It’s known under the brand name Splenda.

Bottom Line: Many different types of artificial sweeteners exist, but not all are approved for use everywhere in the world. The most common include aspartame, sucralose, saccharin, neotame and acesulfame potassium.

Artificial Sweeteners, Appetite and Weight

Artificial sweeteners are often popular among individuals who are trying to lose weight.

However, their effects on appetite and weight vary among studies.

Effects on Appetite

Some people believe artificial sweeteners might actually increase appetite and promote weight gain.

They think artificial sweeteners may be unable to activate the “food reward pathway” needed to make you feel satisfied after you eat.

Because they taste sweet but lack the calories found in other sweet-tasting foods, they’re thought to confuse the brain into still feeling hungry.

Additionally, some scientists think you’d need to eat more of an artificially sweetened food, compared to the sugar-sweetened version, in order to feel full.

It’s even been suggested that sweeteners may cause cravings for sugary foods.

Although these theories are plausible, many recent reports are unable to show that artificial sweeteners increase hunger or calorie intake.

In fact, several studies have found that participants report less hunger and consume fewer calories when they replace sugary foods and beverages with artificially sweetened alternatives.

Bottom Line: Recent reports find that replacing sugary foods or drinks with artificially sweetened ones may reduce hunger and calorie intake.

Effects on Weight

Regarding weight control, some observational studies report a link between consuming artificially sweetened beverages and obesity.

However, randomized controlled studies — the gold standard in scientific research — report that artificial sweeteners may actually reduce body weight, fat mass and waist circumference.

These studies also show that replacing regular soft drinks with sugar-free versions can decrease body mass index (BMI) by up to 1.3–1.7 points.

What’s more, choosing artificially sweetened foods instead of those with added sugar may reduce the amount of daily calories you consume.

Various studies ranging from 4 weeks to 40 months show that this may lead to weight loss of up to 2.9 lbs (1.3 kg).

Artificially sweetened drinks can be an easy alternative for regular soft drink consumers who want to decrease their sugar consumption.

However, opting for diet soda will not lead to any weight loss if you compensate by eating larger portions or extra sweets. If diet soda increases your cravings for sweets, sticking to water might be best.

Bottom Line: Replacing sugar-containing foods and beverages with artificially sweetened ones may help you lose some weight.

Artificial Sweeteners and Diabetes

Diabetics may benefit from choosing artificial sweeteners, which offer the pleasure of sweet taste without the accompanying rise in blood sugar levels.

However, some studies report that drinking diet soda may increase the risk of developing diabetes by 6–121%.

This may seem contradictory, but it’s important to note that all of the studies are observational. They can’t prove artificial sweeteners cause diabetes, only that people likely to develop type 2 diabetes also like to drink diet soda.

On the other hand, many controlled studies show that artificial sweeteners do not affect blood sugar or insulin levels.

So far, only one small study of Hispanic women found a negative effect.

Women who drank an artificially sweetened drink before a sugary drink had 14% higher blood sugar levels and 20% higher insulin levels, compared to those who drank water before the sugary drink.

However, the participants weren’t used to drinking artificially sweetened drinks, which may partially explain the results. What’s more, artificial sweeteners may have different effects based on people’s age or genetic background.

For example, research shows that replacing sugar-sweetened beverages with artificially sweetened ones produced stronger effects among Hispanic youth.

This could be related to the unexpected effect seen on Hispanic women above.

Although not unanimous, the current evidence is generally in favor of artificial sweetener use among diabetics. That said, more research is needed to evaluate the long-term effects in different populations.

Bottom Line: Artificial sweeteners can help diabetics reduce the amount of added sugar in their diets. However, more research is needed into the effects on different populations.

Artificial Sweeteners and Metabolic Syndrome

Metabolic syndrome refers to a cluster of medical conditions including high blood pressure, high blood sugar, excess belly fat and abnormal cholesterol levels.

These conditions increase your risk of chronic diseases such as stroke, heart disease and type 2 diabetes.

Some studies suggest diet soda drinkers could have up to a 36% higher risk of metabolic syndrome.

However, higher-quality studies report that diet soda either has no effect or a protective one.

One recent study provided overweight and obese participants with either a quarter gallon (1 liter) of regular soda, diet soda, water or semi-skimmed milk each day.

By the end of the six-month study, participants drinking the diet soda had striking differences compared to those drinking regular soda.

They weighed 17–21% less and had 24–31% less belly fat, 32% lower cholesterol levels and 10–15% lower blood pressure.

Water had the same benefits as diet soda, compared to regular soda.

Bottom Line: Artificial sweeteners are unlikely to promote metabolic syndrome. Replacing sugary drinks with artificially sweetened ones might actually decrease the risk of several medical conditions.

Artificial Sweeteners and Gut Health

Your gut bacteria play an important role in health, and poor gut health is linked to numerous problems.

These include weight gain, poor blood sugar control, metabolic syndrome, a weakened immune system and disrupted sleep.

The composition and function of gut bacteria varies between individuals and seems to be affected by what you eat, including artificial sweeteners (51, 52).

In one recent study, the artificial sweetener saccharin disrupted the gut bacteria balance in four out of seven healthy participants not used to consuming them.

The four “responders” also showed worse blood sugar control as little as five days after consuming the artificial sweetener.

What’s more, when the gut bacteria from these people were transferred into mice, the animals also developed poor blood sugar control.

On the other hand, the mice implanted with the gut bacteria from “non-responders” had no changes in their ability to control blood sugar levels.

Although interesting, this is the only study to date showing these effects in humans. More studies are needed before strong conclusions can be made.

Bottom Line: Artificial sweeteners may disrupt the balance of gut bacteria in some people, which could increase the risk of disease. However, more studies are needed to confirm this effect.

Artificial Sweeteners and Cancer

A debate has raged since the 1970s about whether there is a link between artificial sweeteners and cancer risk.

The debate was ignited when animal studies found an increased risk of bladder cancer in mice fed extremely high amounts of saccharin and cyclamate.

Luckily, the metabolism of saccharin is different in mice and humans.

Since then, more than 30 studies performed in humans have found no links between artificial sweeteners and the risk of developing cancer.

One such study followed 9,000 participants for 13 years and analyzed their artificial sweetener intake. After accounting for other factors, the researchers found no link between artificial sweeteners and the risk of developing various types of cancer.

A recent review analyzed studies that had been published over an 11-year period. It also did not find a link between cancer risk and artificial sweetener consumption.

This was also evaluated by US and European regulatory authorities. Both agreed that artificial sweeteners, in recommended amounts, do not increase cancer risk.

One exception is cyclamate, which was banned for use in the US after the original mouse bladder cancer study came out in 1970.

Since then, extensive studies in animals have failed to show a cancer link. However, cyclamate was never re-approved for use in the US (1).

Bottom Line: Based on the current scientific evidence, artificial sweeteners are unlikely to increase the risk of cancer in humans.

Artificial Sweeteners and Dental Health

Dental caries — also known as cavities or tooth decay — occur when the bacteria in your mouth ferment sugar. Acid is produced, which can damage tooth enamel.

Unlike sugars, artificial sweeteners do not react with the bacteria in the mouth. This means they do not form acids and therefore do not cause tooth decay.

Research also shows that sucralose is less likely to cause tooth decay than sugar.

For this reason, the US Food and Drug Administration (FDA) authorizes products containing sucralose to claim that they reduce tooth decay.

The European Food Safety Authority (EFSA) states that all artificial sweeteners, when consumed in place of sugar, neutralize acid and help prevent tooth decay.

Bottom Line: Artificial sweeteners, when consumed instead of sugar, decrease the likelihood of tooth decay.

Aspartame, Headaches, Depression and Seizures

Some artificial sweeteners may cause unpleasant symptoms such as headaches, depression and seizures, at least in some individuals.

While most studies find no link between aspartame and headaches, two note that some people are more sensitive than others.

This individual variability may also apply to aspartame’s effects on depression.

For instance, individuals suffering from mood disorders may be more likely to experience depressive symptoms in response to aspartame consumption.

Finally, artificial sweeteners do not increase most people’s seizure risk. However, one study reported increased brain activity in children with absence seizures.

Bottom Line: Artificial sweeteners are unlikely to cause headaches, depression or seizures in most people. However, some individuals could be more sensitive to these effects than others.

Safety and Side Effects

Artificial sweeteners are generally considered safe for human consumption.

They are carefully tested and regulated by US and international authorities to make sure they are safe to eat and drink.

That said, some individuals should avoid consuming them. For example, aspartame contains the amino acid phenylalanine.

Individuals with the rare metabolic disorder phenylketonuria (PKU) cannot metabolize it. People who have PKU should therefore avoid aspartame.

In addition, some people are allergic to the class of compounds that saccharin belongs to, called sulfonamides. For them, saccharin may lead to breathing difficulties, rashes or diarrhea.

Bottom Line: Artificial sweeteners are generally considered safe but should be avoided by people with phenylketonuria or those allergic to sulfonamides.

How B vitamins could boost your memory

Older adults who took vitamin B12 and folic acid supplements for two years had greater improvements on short- and long-term memory tests than adults who did not take the vitamins, according to an Australian study.

The benefits were modest but encouraging, said author Janine Walker, a researcher at Australian National University, of the study published in the American Journal of Clinical Nutrition.

"(Vitamins) may have an important role in promoting healthy ageing and mental wellbeing, as well as sustaining good cognitive functioning for longer on a community-wide scale," said Walker.

The researchers asked more than 700 people aged 60 to 74 years to take a daily dose of folic acid and vitamin B12, or placebo pills that resembled the vitamins. The vitamin dose included 400 micrograms of folic acid and 100 micrograms of vitamin B12, and participants didn't know which they were assigned to take.

The people taking part in the study showed signs of depression, but none had been diagnosed with clinical depression, the researchers said.

"We felt that older people with elevated depressive symptoms were an important cohort to target given evidence that late-life depression is associated with increased risk of cognitive impairment," Walker said.

After 12 months, there seemed to be no difference between the groups in how well people scored on mental tests, including memory, attention and speed.

But after two years, those who took the vitamins showed more, if modest, improvement in their scores on the memory tasks.

For instance, on a short term memory test, those who took the fake pills improved their score from about 5.2 to about 5.5 over two years. Those who took the vitamins increased their test scores from 5.16 to about 5.6.

Short term memory is used to dial a number someone has just told you, while long term memory comes into play when you try to call that number a day or week later.

How does taking vitamins boost brain functioning? 

One idea is that the vitamins reduct the body's levels of a molecule called homocysteine, which is linked to cardiovascular disease and poor cognitive function. The thinking goes that lowering homocysteine could perhaps reduce the cardiovascular risk, and in turn affect mental functioning.

Joshua Miller, a professor at the University of California, Davis, said it's difficult to translate the memory improvement on the tests into real life benefits, with some people likely having larger memory improvements and others much less.

"For any given individual, there may or may not be an effect," he said.

"But on a population level, a small increase in cognitive function can have very real ramifications on the functioning of the population as a whole, and on the costs of healthcare."

Further tests are needed, including whether other groups of people, especially those older than people in the new study, would also benefit from taking vitamins, Walker said.