Which plants protect And Improve our brain health?

Either you are adult, adolescent or after your mid-age, the need of having a healthy, strong and active brain is always there. Leading a busy lifestyle full of responsibilities, endless tasks, plenty of stress and a continuous need to stay productive, go together with a high need to maintain a strong brain and enhance our focus. Unfortunately, depression is also more and more occurring in adolescents.

Apart from that, the fear of growing older and developing a degenerative disease is always behind us. Maintaining and improving our brain health is for sure a very complicated matter, but it’s the Holy Grail nowadays as life expectancy increases. Who would not like to get old and have a sharp brain? Scientists say to keep learning new things like new skills, new languages, or even dancing, exercising or playing music helps a lot. Meditation and socialization play also a big role. Is that all you can do to keep a stronger brain?

How diet affects the human brain function

What about our diet? According to scientists each organism should be considered together with their microbiota (bacteria, archea, protists, fungi and viruses with their genome and their functions) as an inseparable functional unit⁶.

BODY + MICROBES = 1 FUNCTIONAL UNIT

Many scientific studies have shown that what we eat determines our microbiome (all the microbes that “live” in our body) which in turn affects our brain function and even our mood. There is also increasing evidence that our brain and our gut microbiome interact and send signals to each other which possibly affect each other’s functions¹⁹. Thus, a balanced gut microbiome can contribute to healthy ageing¹¹. So, we should get really serious about what we are eating. Not crazy, but for sure develop a critical mind and some healthy habits. Achieving this will allow us to high perform, have better focus and a strong brain until a very old age.

Is a plant-based diet good for your brain?

It has been proven that people who follow a vegan diet are consuming more fiber, beta carotene, vitamin K and C, folate, magnesium, and potassium and have generally a better health¹⁵. However, vegans are at high risk of lacking some important micronutrients, like iron, selenium and iodine³ or vitamin B12, which are extremely important for the good function of the body and the brain¹⁷. Another important benefit of a plant based diet is that it helps beneficial bacteria to get established in our gut and improve our overall health²⁹. The fact that humans have 99,9% similarity in their genome, but their microbiome is 80-90% different is astonishing³⁰!

Consequently, it seems that a plant-based diet could be beneficial against obesity, eating disorders and diet related diseases, such as diabetes and cardiovascular issues. However, it is still not very clear if it has a beneficial impact on our mental and cognitive functions. From preliminary studies, it has been shown that certain plant compounds (phytochemicals) can improve our brain health and help us prevent some degenerative diseases^{7, 13, 31}.

Brain health facts

Two things play a major role in maintaining a healthy brain.

1. Good blood flow, in order to provide oxygen and glucose to the brain and to remove the waste from it.
2. Maintaining healthy neuronal synapses and developing continuously new connections between our neurons (synaptogenesis), in order to enhance brain plasticity and maintain a good memory²⁴.

As we get older, our cognitive function deteriorates due to reduced cerebral blood flow ². This can lead to several neurological disorders, such as brain damage, dementia and Alzheimer’s or Parkinson’s disease². One of the major reasons for this deterioration is the damage of the blood vessels that supply the brain and the spinal cord with freshly oxygenated blood. There is also plenty of evidence showing that synapse deterioration occurs in high rates during Alzheimer’s or other neurological disorders associated with aging¹².

Foods for healthy brain

• Beetroot, spinach, arugula

One factor that contributes to the damage of our blood vessels while getting older is the lack of nitric oxide (NO). Thus, plants with high content of NO generators, like beetroot, can improve the blood flow in our brain and reduce the risk of developing age related diseases.

• Black pepper (Piper nigrum)

It contains piperine, a substance that has great anti-oxidant activity. In several animal studies, piperine was shown to reduce and prevent cognitive malfunctions^{32, 33}.

• Cinnamon

Among the many health benefits that cinnamon has, it contains some components that can protect our brain from oxidative stress, help our neurons to grow and remain healthy, as well as reduce the production of several toxic molecules produced during Alzeihmer’s disease.

• Cocoa powder

Cocoa beans contain more phenolic antioxidants than other foods and have been studied well for their effect on cognition^{8, 21, 27}. They are also rich in other beneficial for our health compounds, such as flavonoids and epicatechins. On the one hand, flavonoids from cocoa have been shown to increase neurogenesis and thus neuroplasticity²⁷. On the other hand, epicatechins can increase the production of NO in our body, which in return helps the healthy function of our blood vessels and the blood flow in our brain⁸.

• Coffee and tea

Both coffee and tea contain phytochemicals with great antioxidant, anti-inflammatory, and neuroprotective effects. It has been proven that chronic intake of both coffee and tea appears to lower the risk of cognitive disorders²⁷.

• Curcuma

A substance called curcumin is the main active component responsible for the brain protective benefits of curcuma. Curcumin is a great antioxidant, it decreases degeneration of the neurons and has been shown to improve locomotor symptoms in insects used as Parkinson’s disease models¹⁴.

• Juices, berries and raw vegetables

They contain natural polysaccharides in their cells which are known also as prebiotics (https://isappscience.org/for-scientists/resources/prebiotics/) -“a substrate that is selectively utilized by host microorganisms conferring a health benefit”⁵. Some well-known polysaccharides are starch, inulin cellulose and peptidoglycans. Although human cells cannot metabolize cellulose and peptidoglycans some microbes that live in our gut can¹⁹. There are numerous studies that have shown their beneficial effect on the brain function and the protection of the CNS⁴.

Apart from the plant polysaccharides, apples, berries, onions, tea, tomatoes, and other plant products contain also another substance named quecertin. Quecertin, is a natural flavonoid with great antioxidant and antimicrobial potential. It was tested together with piperine (from black pepper) in rat models and it was shown that it has promising protective role against neurotoxicity.

• Herbs

Herbs are an important and essential part of the Mediterranean diet, which is considered one of the healthiest in the world. Adding fresh or powdered herbs in our food can boost our memory, reduce sugar levels in our body and prevent brain aneurysms¹. Herbs from the mint family have been well studied for their effect on the brain and they can help to improve the function of our brain as well as prevent Alzheimer’s disease. According to some studies, basil can also help to prevent Parkinson’s disease. Thus, adding fresh or dried herbs in our diet or drinking herbal tea can really help as maintain a strong brain.

• Nuts

Nuts and especially walnuts and Brazil nuts have been tried in clinical trials for their beneficial effects on the human brain²⁶. As they contain high amounts of polyunsaturated fats (PUFAs), like linoleic and α-linolenic acid (18:3n−3), and antioxidant polyphenols they can protect the brain from oxidative and inflammatory stress. On the top of that n–3 PUFAs can protect our neurons, but also stimulate their growth. Other bioactive compounds in walnuts such as arginine, tocopherols, folate, melatonin, and polyphenols can improve our cognitive health because they protect our heart and thus help us maintain a good blood flow. Interestingly, Finally, Brazil nuts contain high amounts of Selenium, a mineral with great antioxidant properties which is also part of some proteins (selenoproteins), important for the brain function²⁶. Interestingly, it is shown from several scientific studies that elderly^{10, 23} or middle-aged²² people who consumed nuts ≥5 times per week had improved global cognition and memory than less frequent consumers.

• Olive oil

According to randomized clinical trials, the Mediterranean diet is one of the healthiest in the world for preventing diseases and living longer. Extra virgin olive oil is an essential part of this diet and according to scientific studies adding it in our daily diet can improve cognitive function in the short term¹⁵ and favour global cognition16 in the long term.

• Pickles, Kombucha, fermented cabbage

Probiotics are health promoting bacteria that live in our gut. There is a growing number of scientific studies that show the positive effect of probiotics on the mood, cognition and brain function¹⁹.
You can usually find probiotics in high amounts in natural yoghurt and some fermented cheeses. However, there are also several well-known foods from different countries which follow a plant based diet. For example, pickles, the well-known Chinese tea Kombucha, fermented cabbage (known as sauerkraut in German or Kimchi in Korean) and sourdough bread.

• Vitamin B rich foods

Luck of folate, vitamin B12 and vitamin B6 have been directly related to cognitive deficit in aging. Several studies have also proven that supplementing the diet of older people with reduced cognition with B vitamins had positive effects. Thus, consuming green leafy vegetables, avocados, eggs, pulses and other foods rich in B vitamins, can help you prevent or improve cognitive function, and potentially depressive symptoms while ageing²⁰.

Medicinal Plants with potential neuroprotective action

The following plants have been tested in animal studies for their effect on neurodegenerative diseases like Alzheimer’s and Parkinson. Although these plants have been used for years in the Ayuverdic and Chinese medicine for the treatment of several diseases and the scientific results are promising, further research is needed. Thus, always ask your doctor before taking supplements of such plants²⁵.

• Acanthus ebracteatus
• Ginkgo biloba L.
• Panax ginseng
• Bacopa monnieri
• Centella asiatica
• Cleistocalyx nervosum var. paniala
• Pueraria mirifica
• Rhinacanthus nasutus
• Streblus asper

Take home message

There is still not clear evidence that a completely plant-based diet is beneficial for our body and brain health. However, people who follow a plant-based diet have different gut microbiome with higher microbial diversity which is beneficial for health. For sure, a diet rich in a variety of foods, with plenty of fruits, vegetables, whole grains, herbs, spices, probiotics, nuts and olive oil can help you maintain a strong brain and a good mood.

Of course, diet alone is not enough for a good brain health. Regular exercise, meditation and avoiding unhealthy foods like refined carbohydrates, processed foods, trans fats and alcohol is also very important to keep your brain sharp and strong.

Tips & Tricks

• Increase brain memory: If you or someone close to you is suffering from memory loss or other cognitive dysfunctions, it could be helpful to combine some of the above foods and add them to the daily diet for long-term (>60 days). For example, combining blueberries with walnuts could have immediate benefits to the brain function²⁷.

Looking for some tasty and healthy recipes to include some of the above  foods in your diet? Here are some ideas:

– Pink salad with beetroot

– Authentic Indian Chai

– Cauliflower curry with ginger, garlic and many different spices

– Pumpkin curry with ginger, garlic, cinnamon and many other spices

References

1. Czekajło A. Role of diet-related factors in cerebral aneurysm formation and rupture. Rocz Panstw Zakl Hig. 2019;70 (2):119-126.
2. Clifford T, Howatson G, West DJ, Stevenson EJ. The potential benefits of red beetroot supplementation in health and disease. Nutrients. 2015;7(4):2801-2822.
3. Fallon N, Dillon SA. Low Intakes of Iodine and Selenium Amongst Vegan and Vegetarian Women Highlight a Potential Nutritional Vulnerability. Front Nutr. 2020;7:72.
4. Gao QH, Fu X, Zhang R, Wang Z, Guo M. Neuroprotective effects of plant polysaccharides: A review of the mechanisms. Int J Biol Macromol. 2018 Jan;106:749-754.
5. Gibson, G., Hutkins, R., Sanders, M. et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics. Nat Rev Gastroenterol Hepatol 2017; 14, 491–502.