There is a protein found in the brain called brain-derived neurotrophic factor, or, more commonly, BDNF. It is active in three areas of the brain:

  1. Hippocampus
  2. Cortex
  3. Forebrain

Between them, these three areas are responsible for learning, memory, and higher thinking. The activity of BDNF in these three areas is essential for memory. BDNF also has a key role in maintaining neuroplasticity and neuronal synapses. It supports the survival of existing neurons, and encourages the growth, regeneration and creation of new neurons. It helps us to think, to concentrate, or memorise and recall, and to be happy.

Some people have low amounts of BDNF. The reason is both genetic and due to lifestyle. About 30% of people will have a genetic variation that means they are prone to low BDNF, while others will live a life that promotes low BDNF. When BDNF runs low people find it more difficult to remember, to recall, or may feel slightly depressed. If BDNF runs lows over an extended period of time, perhaps a few decades, then the brain responds by producing amyloid plaque, and the first symptoms of Alzheimer’s disease begin.

We know from human studies on Alzheimer’s disease that the three areas of the brain that are affected are the hippocampus, cortex, and forebrain. These are the exact areas of the brain where BDNF should be active. As the cortex and the hippocampus shrivel up and shrink, memory is impaired, especially thinking and planning, and new memories are hard to form. This is why Alzheimer’s disease patients can often remember their childhood, but cannot remember someone they’ve just met or more recent experiences.

Now, this doesn’t mean that BDNF is the missing link that is the cause of Alzheimer’s disease or memory loss, because Alzheimer’s disease is caused by numerous lifestyle and genetic assaults on the brain. But it does mean that if you increase levels of BDNF, especially if you have the genetic variation that produces less BDNF, then you reduce your risk of Alzheimer’s disease. Even if you are younger, and not concerned about permanent memory loss, you’ll find that increasing BDNF will elevate mood, thought, planning, motivation, memory, and recall. You’ll probably become a more motivated, productive person, and take less time to do intellectual tasks.

How to Increase BDNF Naturally


  1. Exercise. This is by far the most effective way to increase BDNF. All the indications we have, all the studies, bar none, show that low intensity exercise is superior. It improves synaptic plasticity in the brain in a way that high intensity exercise does not. Even exercise with the heart rate as low as 50% of maximum — effectively a brisk walk — increases BDNF and lends credence to the traditional wisdom: going for a walk clears the mind. To increase BDNF the best form of exercise is any that you enjoy, done three times a week, with your heart rate between 60-70% of its maximum rate for thirty minutes each time. This is quite easy, light exercise. It’s not pushing oneself. Recovery will be good. You could get a heart rate monitor, or use an app on your phone to keep your heart rate in the 60-70% zone. Alternatively, you can measure your heart rate by your breath. The way to do this to breath in and out easily through your nose while exercising. If you have to breathe through your mouth then you are exercising too hard to produce much BDNF.
  2. Sleep. Optimum amounts of sleep, specifically slow wave (stage 3/4) deep sleep increase BDNF. The more sleep deprived, stimulated, or lack of deep sleep a person has, the less BDNF they produce. This lack of BDNF production, due to lack of sleep, is enhanced in people with the sub-optimal BDNF gene. This means planning, working memory, and lack of ability to lay down long-term memories is compromised. Adequate sleep also increases testosterone, which in turn increases BDNF.
  3. Fasting. Alternate day or intermittent fasting increases BDNF by between 50 – 400%. This is conditional on only having one 600 kcal meal in a 24-hour period. It is probable that smaller 16 hour fasts will also increase BDNF. This is not so hard: just skip breakfast. If you eat at 8.00 pm the previous night, skip breakfast, then take lunch at 12.00 pm, you have your 16 hours. This smaller 16 hour fast can be done on a near daily basis, but the absolute minimum is allowing for 12 hours between the last snack at night and the first meal of the next morning.
  4. Ketosis. This is when the body and brain runs on ketones rather than glucose. To be in ketosis you need to be on a very low carbohydrate diet, and preferably in a slight calorie deficit. We do not recommend mountains of fat, butter, and coconut oil to get into ketosis, as some people, due to important genetic variations, should have less fat than others. We also recommend that ketosis is only entered for some days of the week, or some months of the year. The practice of many traditional people, either due to famine and scarcity of food, the winter seasons, or their seasonal diet was to be in ketosis some of the time, while being out of ketosis at other times. This is the balance we recommend.
  5. Stress. Stress obliterates BDNF. There has to be stress management techniques.
  6. Sun. Exposure to the spring and summer sun increases BDNF. It is less clear whether supplemental vitamin D increases BDNF. This suggests that walking in the sun is especially beneficial.
  7. Early life experience. If you have children then you must show them love and give them your time, even if it means tearing yourself away from that ‘really important message’ that just arrived on your phone. There should be healthy physical contact between parent and child. A fascinating recent study showed that early life stress or neglect, combined with low BDNF, leads to memory impairment and depression. If you were neglected as a child, then it’s important to try and find love later in life, to address any issues from your childhood, and to take steps to ensure your mood and emotions are good. Acupuncture is one therapy we recommend for releasing old emotions.
  8. The key dietary intervention is omega-3 from oily fish. We recommend this is got from actual fish had 3 or 4 times a week. Wild salmon, herring, north east Atlantic mackerel, black cod, sardines, wild trout, and anchovies are all good choices. They are all low in mercury.
  9. The key dietary avoidance is junk food and sugar. Both work together to lower BDNF.

Finally, if BDNF levels are increased, women (not men) are more likely to be in love. If the above advice is followed, BDNF is increased, love is increased, vitality improved, and depression reduced. All key ingredients for a healthy life and a healthy marriage.

Therefore, increasing or maintaining levels of BDNF is important for everyone who wants a healthy brain, optimal productivity, elevated mood and motivation, and a large dose of love. Some people with the genetic variation that lowers BDNF will need to pay extra attention to these recommendations, but even they can experience increased ardour and passion.