*Raising histamine levels boosts long-term memory
The foods we eat can have a big impact on the structure and health of our brains. Eating a brain-boosting diet can support both short- and long-term brain function.The brain is an energy-intensive organ, using around 20 percent of the body’s calories, so it needs plenty of good fuel to maintain concentration throughout the day.
The brain also requires certain nutrients to stay healthy. Omega-3 fatty acids, for example, help build and repair brain cells, and antioxidants reduce cellular stress and inflammation, which are linked to brain aging and neurodegenerative disorders, such as Alzheimer’s disease.
This article first published by Medical News Today explores the scientific evidence behind 12 of the best brain foods.
1. Oily fish
Oily fish are a good source of omega-3 fatty acids. Omega-3s help build membranes around each cell in the body, including the brain cells. They can, therefore, improve the structure of brain cells called neurons. A 2017 study found that people with high levels of omega-3s had increased blood flow in the brain. The researchers also identified a connection between omega-3 levels and better cognition, or thinking abilities.
These results suggest that eating foods rich in omega-3s, such as oily fish, may boost brain function.Examples of oily fish that contain high levels of omega-3s include: salmon; mackerel; tuna; herring; and sardines.People can also get omega-3s from soybeans, nuts, flaxseed, and other seeds.
2. Dark chocolate
Dark chocolate contains cocoa, also known as cacao. Cacao contains flavonoids, a type of antioxidant.Antioxidants are especially important for brain health, as the brain is highly susceptible to oxidative stress, which contributes to age-related cognitive decline and brain diseases.
Cacao flavonoids seem to be good for the brain. According to a 2013 review, they may encourage neuron and blood vessel growth in parts of the brain involved in memory and learning. They may also stimulate blood flow in the brain.Some research also suggests that the flavonoid component of chocolate may reverse memory problems in snails. Scientists have yet to test this in humans.
However, a 2018 study in humans also supports the brain-boosting effects of dark chocolate. The researchers used imaging methods to look at activity in the brain after participants ate chocolate with at least 70 percent cacao.The researchers concluded that eating this type of dark chocolate may improve brain plasticity, which is crucial for learning, and may also provide other brain-related benefits.
Like dark chocolate, many berries contain flavonoid antioxidants. Research suggests that these may make the berries good food for the brain. Antioxidants help by reducing inflammation and oxidative stress. The antioxidants in berries include anthocyanin, caffeic acid, catechin, and quercetin.
A 2014 review notes that the antioxidant compounds in berries have many positive effects on the brain, including: improving communication between brain cells; reducing inflammation throughout the body; increasing plasticity, which helps brain cells form new connections, boosting learning and memory; and reducing or delaying age-related neurodegenerative diseases and cognitive decline.Antioxidant-rich berries that can boot brain health include: strawberries; blackberries; blueberries; blackcurrants; and mulberries.
4. Nuts and seeds
Mixed nuts and seeds on wooden spoon over table, including pine nuts, almonds, pistachios, and cashews. Nuts and seeds are a plant-based source of healthful fats and proteins.Eating more nuts and seeds may be good for the brain, as these foods contain omega-3 fatty acids and antioxidants.
A 2014 study found that a higher overall nut intake was linked to better brain function in older age.Nuts and seeds are also rich sources of the antioxidant vitamin E, which protects cells from oxidative stress caused by free radicals.As a person ages, their brain may be exposed to this form of oxidative stress, and vitamin E may therefore support brain health in older age.A 2014 review found that vitamin E may also contribute to improved cognition and reduced risk of Alzheimer’s disease.The nuts and seeds with the highest amounts of vitamin E include: sunflower seeds; almonds; and hazelnuts. Fully exploring vitamin E’s effects on the brain will require further research.
5. Whole grains
Eating whole grains is another way to benefit from the effects of vitamin E, with these grains being a good source of the vitamin.Whole-grain foods include: brown rice; barley; bulgur wheat; oatmeal; whole-grain bread; and whole-grain pasta.
Coffee is a well-known concentration aid — many drink it to stay awake and encourage focus.The caffeine in coffee blocks a substance in the brain called adenosine, which makes a person feel sleepy.Beyond boosting alertness, a 2018 study suggests that caffeine may also increase the brain’s capacity for processing information.The researchers found that caffeine causes an increase in brain entropy, which refers to complex and variable brain activity. When entropy is high, the brain can process more information.Coffee is also a source of antioxidants, which may support brain health as a person gets older. One study has linked lifelong coffee consumption with reduced risk of: cognitive decline; stroke; Parkinson’s disease; and Alzheimer’s disease.Caffeine can, however, affect a person’s sleep and doctors do not recommend caffeine consumption for everyone.
A source of healthful unsaturated fat, avocados may support the brain. Eating monounsaturated fats may reduce blood pressure, and high blood pressure is linked with cognitive decline.Thus, by reducing high blood pressure, the unsaturated fats in avocados may lower the risk of cognitive decline.Other sources of healthful unsaturated fats include: almonds, cashews, and peanuts; flaxseed and chia seeds; soybean, sunflower, and canola oils; walnuts and Brazil nuts; and fish.
Peanuts are a legume with an excellent nutritional profile. They contain plenty of unsaturated fats and protein to keep a person’s energy levels up throughout the day.Peanuts also provide key vitamins and minerals to keep the brain healthy, including high levels of vitamin E and resveratrol. Resveratrol is a natural non-flavonoid antioxidant found in peanuts, mulberries, and rhubarb. Evidence from a review article suggests that resveratrol can have protective effects, such as helping to prevent cancers, inflammation, and neurological diseases, including Alzheimer’s and Parkinson’s.
Enjoyed by many for breakfast, eggs can be an effective brain food.They are a good source of the following B vitamins: vitamin B-6; vitamin B-12; and folic acid.Recent research suggests that these vitamins may prevent brain shrinkage and delay cognitive decline.
Broccoli and other cruciferous vegetables are rich in fiber and nutrients. As well as being a low-calorie source of dietary fiber, broccoli may be good for the brain.Broccoli is rich in compounds called glucosinolates. When the body breaks these down, they produce isothiocyanates. Isothiocyanates may reduce oxidative stress and lower the risk of neurodegenerative diseases.
Broccoli also contains vitamin C and flavonoids, and these antioxidants can further boost a person’s brain health.Other cruciferous vegetables that contain glucosinolates include: brussels sprouts; bok choy; cabbage; cauliflower; turnips; and kale.
Leafy greens, including kale, may support brain health. Like broccoli, kale contains glucosinolates, and leafy greens also contain other key antioxidants, vitamins, and minerals. This is why many consider kale to be a superfood.
12. Soy products
Soybean products are rich in a particular group of antioxidants called polyphenols. Research has linked polyphenols with a reduced risk of dementia and improved cognitive abilities in regular aging processes.Soy products contain polyphenols called isoflavones, including daidzein and genistein. These chemicals act as antioxidants, providing a range of health benefits throughout the body.
Supplements for brain function
In addition to making dietary changes, some people consider taking supplements to improve their brain function. But do these supplements actually work?Taking vitamins B, C, or E, beta-carotene, or magnesium may improve brain function if a person has a deficiency in any of them. If a person does not have a deficiency, these supplements are unlikely to improve mental performance.Research suggests that taking ginseng may improve this performance. However, further studies are needed before doctors can recommend ginseng to enhance brain function.
The foods listed above may help improve a person’s memory and concentration. Some may also reduce the risk of stroke and age-related neurodegenerative diseases, such as Alzheimer’s and Parkinson’s.Some of the foods contain compounds such as healthful fatty acids, which can help improve the structure of brain cells called neurons. Other compounds, such as sugars and saturated fats, may damage brain cell structures.
Brain-boosting foods tend to contain one or more of the following: antioxidants, such as flavonoids or vitamin; B vitamins; healthful fats; and omega fatty acids.Beyond adjusting the diet, a person can optimize their brain function by: not eating too much or too little; getting enough sleep; keeping hydrated; exercising regularly; reducing stress through yoga, mindfulness, or meditation; and reducing alcohol intake.Eating a brain-boosting diet will also provide many benefits for the entire body.
Raising histamine levels boosts long-term memory
According to a fascinating new study, taking a drug that increases histamine levels in the brain could improve performance in long-term memory tests.
Mast cell filled with histamine granules
Histamine carries out multiple roles in the body. Perhaps most famous for its role in the immune system, histamine also helps regulate gut function and acts as a neurotransmitter. Thanks to their role in allergic reactions, medications that reduce histamine levels — antihistamines — are commonplace.
Drugs that boost histamine levels are less common, but doctors sometimes prescribe them to treat dizziness.
According to the latest study, however, histamine-boosting drugs might, one day, become more prevalent.Over recent decades, researchers have demonstrated an interesting relationship between increased histamine and improvements in memory. However, currently, they do not fully understand the interaction.
Researchers hope that by studying the interplay between the two, they might glimpse innovative ways of treating individuals with impaired memories, such as dementia.A new study set out to unwrap another layer of this phenomenon. The scientists wanted to understand how histamine impacts long-term memory.The team was headed up by Prof. Yuji Ikegaya and Hiroshi Nomura, Ph.D., from the University of Tokyo in Japan. This week, the journal Biological Psychiatry published the findings.
To investigate, they recruited 38 males and females, all in their mid-20s. The researchers asked the participants to memorize images of everyday objects, such as wristwatches and glasses.A few days later, they tested the participants. The researchers showed them some of the original images mixed in with some that they had not seen before. The researchers asked the participants to identify which of the pictures they had seen in the initial session.
Then, seven–nine days later, the researchers tested the participants again. However, this time, before the trial, the participants took either a placebo or a drug that boosted histamine levels in the brain.As expected, histamine did have a positive impact on some participant’s memory test scores. For individuals with poorer memories, the histamine boost helped them to recognize more images than they did in the first round of tests.
It is also worth noting that histamine only boosted long-term memory — it did not improve any other cognitive abilities.One finding from the study is especially intriguing. The researchers showed the participants a particular image. However, a few days later, they failed to remember seeing that image. Then, around one week later, after histamine treatment, they were able to recall that they had seen the image.“To any students thinking about using this drug as a study aid, I must warn them to first always protect their health, and second to realize that we have not tested whether this drug helps anyone learn or memorize new things.”
However, not all individuals saw an improvement. Those who had performed best in the pre-medication memory tests saw a drop in performance after histamine treatment.And, for all participants, whether high or low scorers, images that were easiest to recall in the pre-medication trials became harder to recollect after boosting histamine levels.
The researchers believe that this surprising contradiction might involve something called stochastic resonance.If a signal is too weak for a sensor to detect, stochastic resonance can help boost it. It works by adding white noise to the signal. The original signal’s frequencies resonate with the white noise, lifting it above the rest of the white noise, making it easier to detect.Prof. Ikegaya and his colleagues believe that memory works in two ways; firstly, it is a “digital” system — yes or no — it is possible to recall the memory, or it is not.
At the same time, the brain can store information as a gradient — nerves do not fire until activity levels reach a certain threshold. Before reaching this threshold, we cannot remember, but once the levels have exceeded the threshold, we can.The scientists think that histamine might push the gradient past the point that triggers the neurons to fire. In this way, a latent memory — a stored memory that we cannot access — becomes accessible.
Conversely, if a memory is already above the gradient, adding extra histamine produces too much noise, and the additional nerve activity hinders memory recall.In another part of their experiment, the researchers studied mice. If a mouse has two toys — one that is familiar and one that is new — they will preferentially play with the new one. However, after three days, the mice forget which is the newest and give the toys equal attention.Knowing this, the researchers treated mice with one of two histamine-boosting drugs: thioperamide or betahistine.
After treatment, rather than forgetting the new toys within 3 days, they remembered them for 28 days. The effect on memory did not last indefinitely, though — on day 29, they, once again, treated all toys as new.When they took a look at the brains of the mice, they saw that histamine levels were particularly high in a region called the perirhinal cortex.
This area of the brain is involved in processing sensory information, perception, and is vital for memory.Although this avenue of research is relatively new, the scientists hope that it could have wider implications. Understanding how histamine influences recall might help design treatments for Alzheimer’s and other types of dementia.