Jodie is a mum, nutritionist and science-nerd with a Bachelor of Science and a Postgraduate Diploma of Human Nutrition. She has a passion for understanding the biological mechanisms underlying mood disorders and deciphering the scientific efficacy of natural approaches to healing. Learn more about Jodie here.
Over the past week, I’ve been super excited to indulge my science brain again. Something I’ve sincerely missed since becoming a mother – time and energy simply haven’t permitted this science nerd luxury.
The past week I rediscovered this wonderful protein/gene, BDNF (brain-derived neurotropic factor) and had to eagerly share this information with you. I was drawn to BDNF due to its role in mitigating depression, and the post-mortem studies, which showed lower levels of BDNF in individuals who committed suicide (Dwivedi 2009; Dunham 2009). If you don’t know my background – I lost my mother to suicide.
So down to the fun stuff… first with a quick background on BDNF.
WHAT IS BDNF? WHAT DOES IT DO?
BDNF aka. Brain-Derived Neurotropic Factor
BDNF is an important growth factor for the brain, especially in the hippocampus and cortex. It supports neuronal plasticity, growth and survival, and strengthens communication between neurons. It is also involved in learning, memory acquisition, and maintenance/access of long-term memory. BDNF is essential to healthy, optimal brain function.
The brain continues to reorganise itself and create new neural connections. This phenomenon is known as neuronal plasticity. Neurotropic factors, such as BDNF, play an important role in regulating and enabling this process.
CONNECTION BETWEEN DEPRESSION & BDNF
Low levels of BDNF have been repeatedly correlated with depression, and suicide, in scientific research. Lower levels are found in peripheral blood samples of people struggling with depression (Lee 2007; Yoshida 2012). Low levels are also found in central brain regions, specifically the hippocampus, in postmortem studies. This reduced BDNF in the hippocampus correlates with smaller hippocampal volumes (Steffens 2000). The hippocampus plays important roles in regulating learning, memory, emotions and the hypothalamic-pituitary-adrenal (HPA) axis.
Lastly, studies assessing the efficacy of particular antidepressant medication and physical activity interventions show upregulation of BDNF consistent with the time course of therapeutic response (Russo-Neustadt 1999).
Low BDNF levels have also been connected to Alzheimer’s, dementia, epilepsy, bipolar disorder, anorexia nervosa, schizophrenia, Huntington’s Disease, and OCD.
10 WAYS TO NATURALLY BOOST YOUR BDNF LEVELS
(1) Reduce Stress.
BDNF levels are significantly influenced by stress. Indeed, many pertinent researchers speculate that low BDNF levels in depressive patients are a downstream outcome of prolonged psychosocial stress. Research demonstrates that BDNF is reduced in response to many different types of stress – both acute (short-term, single stress) and chronic. Some specific situations that have been investigated include social isolation, social defeat, swim stress, unpredictable, footshock, and maternal deprivation (Duman 2006). There are many ways to reduce your stress load – usually this is unique and specific to individual circumstances. What steps can you take today to start reducing your stress?
(2) Intense Exercise.
BDNF is highly responsive to physical activity and therefore, this is my #2 most important action to boost your BDNF levels. After reading the research, I was motivated to hit the gym for a 30 minute cycle session with some high intensity intervals. There is ongoing debate around the specific type and duration of exercise for therapeutic BDNF benefits. Currently intense physical activity appears to be optimal. However due to the other, extensive benefits of exercise – any intentional movement is worthwhile.
(3) Intermittent Fasting.
Intermittent fasting is any periodic abstinence or reduction of food intake. Although current scientific evidence is scarce, intermittent fasting looks promising to improve BDNF levels (Mattson 2003).
(4) Intellectual Stimulation.
Exercising or indulging your brain with intellectual tasks stimulates BDNF – as we’d expect due to its role in learning and memory (Korol 2013). So keep reading!
(5) Warmth, Sauna and Sun.
An analysis of 2,851 individuals in the Netherlands found that blood BDNF increased in the spring and summer and decreased in the fall and winter (Molendijk 2012). The mechanism is unclear.
The effects do not appear to be mitigated through vitamin D. But warmth / heat seems to be important. A study conducted in chicks showed heat exposure boosted BDNF levels (Katz 2006).
Actually it was this podcast by Rhonda Patrick, called Sauna Use and Building Resilience to Stress, that re-sparked my interest in BDNF.
(6) Niacin.
Although the science is scarce, niacin (vitamin B3) is a promising mediator for raising expression of BDNF and its receptor, tropomyosin-related kinase B (TrkB) (Fu 2014). Niacin rich-foods include turkey, chicken, cheese, mushrooms, liver, fish, peanuts, etc.
(7) Omega 3 Fatty Acids, DHA.
The inclusion of omega-3 fatty acids in the diet help support BDNF levels. Studies involving injury to the brain demonstrate improved neuronal survival and plasticity corresponding with higher BDNF levels (Kumar 2014; Wu 2004).
One of the most effective ways to get omega 3 fatty acids in your diet is to consume oily fish. To further boost or support your levels, non-fish sources include walnuts, chia seeds, flax seeds, etc.
(8) Curcumin.
Curcumin – better-known as the active anti-inflammatory component of turmeric – appears to promote BDNF expression (Wang 2010). More research is needed on this topic.
(9) Phytochemicals.
A few phytochemicals are promising promoters of healthy BDNF levels. Resveratrol, found primarily in red grapes, has been found to improve BDNF levels (Moriya 2011). Anthocyanins in blueberries similarly raise BDNF (Rendeiro 2013).
(10) Sleep.
Adequate sleep is important for healthy BDNF levels. While a little acute sleep loss might boost levels of BDNF, regular, chronic sleep deprivation is bad news for healthy BDNF (Zielinski 2014).
CONTRARY
Studies have shown increased levels of BDNF in the amygdala and nucleus accumbens of individuals with depression. I’ll want to read up on this at a later date.
CONCLUSION
Reduced expression of BDNF is associated with depression and other mental health conditions, and is important for overall brain health. There are scientific, natural ways to boost your levels of BDNF. Although it is certainly true that these actions exert their positive effects through other biochemical and physiology pathways in addition to BDNF. Nevertheless, my investigation into BDNF, specifically, has encouraged me (and hopefully will encourage others) to be more proactive with these healthy actions.
RESOURCES:
Dunham, JS, Deakin, JF, Miyajima, F, Payton, A, Toro, CT. 2009. Expression of hippocampal brain-derived neurotrophic factor and its receptors in Stanley consortium brains, J Psychiatric Research; 43(14): 1175–1184.
Dwivedi, Y, Rizavi, HS, Zhang, H, et al. 2009. Neurotrophin receptor activation and expression in human postmortem brain: effect of suicide,” Biological Psychiatry; 65(4): 319–328.
Lee, BH, Kim, H, Park, SH, Kim, YK. 2007. Decreased plasma BDNF level in depressive patients, J Affective Disorders; 101(1–3): 239–244.
Yoshida, T, Ishikawa, M, Niitsu, T, et al. 2012. Decreased serum levels of mature brain-derived neurotrophic factor (BDNF), but not its precursor proBDNF, in patients with major depressive disorder, PLoS One; 7(8): e42676.
Steffens, DC, Byrum, CE, McQuoid, DR, et al. 2000. Hippocampal volume in geriatric depression, Biological Psychiatry; 48(4): 301–309.
Russo-Neustadt, A, Beard, RC, Cotman, CW. 1999. Exercise, antidepressant medications, and enhanced brain derived neurotrophic factor expression, Neuropsychopharmacology; 21(5): 679–82.
Duman, SR and Monteggia, LM. 2006. A neurotrophic model for stress-related mood disorders, Biol Psychiatry; 59(6): 469–478.
Mattson, MP, Duan, W, Guo, Z. 2003. Meal size and frequency affect neuronal plasticity and vulnerability to disease: cellular and molecular mechanisms. J Neurochem; 84: 417–431.
Korol, DL, Gold, PE, Scavuzzo, CJ. 2013. Use it and boost it with physical and mental activity. Hippocampus; 23(11): 1125–35.
Molendijk, ML, Haffmans, JPM, Bus, BAA, Spinhoven, P, Penninx, BWJH, Prickaerts, J, Oude Voshaar, RC, Elzinga, BM. 2012. Serum BDNF concentrations show strong seasonal variation and correlations with the amount of ambient sunlight, PLoS One; 7(11): e48046.
Katz A, Meiri, N. 2006. Brain-derived neurotrophic factor is critically involved in thermal-experience-dependent developmental plasticity, J Neurosci; 26(15): 3899–907.
Fu, L, Doreswamy, V, Prakash, R. 2014. The biochemical pathways of central nervous system neural degeneration in niacin deficiency. Neural Regen Res; 9(16): 1509–1513.
Wang, R, Li, YH, Xu, Y, Li, YB, Wu, HL, Guo, H, Zhang, JZ, Zhang, JJ, Pan, XY, Li, XJ. 2010. Curcumin produces neuroprotective effects via activating brain-derived neurotrophic factor/TrkB-dependent MAPK and PI-3K cascades in rodent cortical neurons, Prog Neuropsychopharmacol Biol Psychiatry; 34(1): 147–53.
Moriya, J, Chen, R, Yamakawa, J, Sasaki, K, Ishigaki, Y, Takahashi, T. 2011. Resveratrol improves hippocampal atrophy in chronic fatigue mice by enhancing neurogenesis and inhibiting apoptosis of granular cells, Biol Pharm Bull. 2011; 34(3): 354–9.
Rendeiro, C, Vauzour, D, Rattray, M, Waffo-Téguo, P, Mérillon, JM, Butler, LT, Williams, CM, Spencer, JP. 2013. Dietary levels of pure flavonoids improve spatial memory performance and increase hippocampal brain-derived neurotrophic factor, PLoS One; 8(5): e63535.
Zielinski, MR, Kim, Y, Karpova, SA, McCarley, RW, Strecker, RE, Gerashchenko, D. 2014. Chronic sleep restriction elevates brain interleukin-1 beta and tumor necrosis factor-alpha and attenuates brain-derived neurotrophic factor expression, Neurosci Lett; 580: 27–31.
Koo, J, Labonté, B, Engmann, O, Calipari, ES, Juarez, B, Lorsch, Z, Walsh, JJ, Friedman, AK, Yorgason, JT, Han, MH, Nestler, EJ. 2015. Essential role of mesolimbic brain-derived neurotrophic factor in chronic social stress-induced depressive behaviors, Biol Psychiatry; 80(6): 469–478.
