Low mood and depression are increasingly prevalent symptoms of 21st century living. While the current statistics from the Center for Disease Control show one in ten people suffer from depression, in clinical practice we see much higher rates of people struggling with unreported low mood or depressive symptoms.
The World Health Organization has estimated that by the year 2050, one-third of the global population will suffer from either anxiety or depression. What is going on? Why are we more prone to depression today than in generations past?
As with any complex condition, there are many factors at play that conspire to create an environment where low mood and depression can thrive. Let’s look at how a Paleo diet can lay the framework for better mental health by addressing influential systems of the body.
AVOID BLOOD SUGAR AND INSULIN DYSFUNCTION
Today, 75% of the North American population are classified as overweight or obese and the annual consumption of processed and simple sugars tops a whopping 160 pounds of sugar per person. This leads to worsening blood sugar control and insulin dysfunction. Research from Scandinavia has uncovered a clear association between elevated HbA1c (a three-month average of blood sugars) and insulin levels with increased risk of depression. A recent study found that young men with insulin resistance were three times more likely to suffer from severe depression.1
Another study in Diabetes Care of over 4,000 people showed depressive symptoms were associated with higher fasting and 30-minute insulin levels.2 The authors specifically noted that antidepressant medications did not alter this association because the medications target neurotransmitters (e.g. serotonin, dopamine) and do not address blood sugar and insulin dysfunction.
Adopting a Paleo diet can dramatically improve blood sugars and insulin levels, an important first step for reducing risk factors for low mood and depression.
COOL LOW-GRADE SYSTEMIC INFLAMMATION
Inflammation is another potential root cause of low mood. Low-grade systemic inflammation leads to the over-production of pro-inflammatory cytokines that are associated with depression.3 The prestigious New England Journal of Medicine recently published a review of the growing connection between chronic inflammation and the development of today’s most common chronic diseases, including depression.4 The current medical literature tells us that if you are overweight or obese, you likely have low-grade systemic inflammation.5
A Paleo diet’s high nutrient density provides a robust intake of antioxidants that help to cool inflammation and reduce the damaging effects of reactive oxygen species (ROS) produced during the inflammatory response. A Paleo diet is also a rich source of anti-inflammatory omega-3 fats that support positive mood. Studies show low levels of omega-3 fats are associated with a chronic stress state and increased risk of depression.6
PROMOTE A HEALTHY GUT
The microflora of the gut plays a key role in your health and is in constant communication with the brain. Key neurotransmitters targeted by medications for improving symptoms of depression – serotonin and dopamine – are actually concentrated in the gut. The research shows that if you are overweight, you will likely have poor zonulin function, a key molecule that regulates gut permeability.7 Poor zonulin function leads to symptoms of a leaky gut, which exacerbates inflammatory levels and can contribute to the cytokine storm that leads to low mood and depression.
You don’t need to be overweight to suffer from leaky gut. The research is clear that chronic or excessive use of NSAIDs – non-steroidal anti-inflammatory drugs – like ibuprofen and naproxen are also a direct cause of leaky gut, which will worsen inflammation.8,9 A Paleo approach to eating supports the growth of good gut bacteria and, therefore, superior intestinal health.
OVERCOME A SEDENTARY LIFESTYLE
Movement is a critical component of mental health and overall wellbeing. Busy workdays make it difficult for people to find time to exercise, however this is a critical component of any mental health plan. A recent meta-analysis of 92 studies on more than 4,310 people showed that light to moderate exercise significantly reduced the incidence of depression.10 Try adding 15-20 minute walks at lunch or the end of your day to increase your activity level.
Strength training can also play a key role in mental health. Basic movements like squatting, lunging, bending, pushing, and pulling are deeply engrained in our DNA and exert tremendous positive benefit on multiple systems of the body: improving blood sugars and insulin, reducing inflammation, boosting testosterone (low levels have been associated with depression), and supporting healthy gut flora. If you’re not active, start slowly with 10-20 minutes of strength training 2-3 times weekly and focus on bodyweight type movements.
There is no “magic bullet” to fix depression. It’s a complex multi-factorial condition that is impacted by numerous systems of the body. By addressing blood sugar imbalances, weight gain, inflammation and dysbiosis, a Paleo diet can provide the body with the building blocks it needs to support positive mood.
If you suffer from depression, talk to your doctor about how you can incorporate a Paleo diet and exercise, along with treatment into your action plan.
1. Timonen. M et al. Insulin resistance and depressive symptoms in young adult males: Findings from Finnish military conscripts. Psychosom Med 69(8):723-28.
2. Pyykkonen AJ et al. Depressive symptoms, antidepressant medication use, and insulin resistance: the PPP-Botnia Study. Diabetes Care. 2011 Dec;34(12):2545-7.
3. Felger J, Lotrich FE. Inflammatory cytokines in depression: neurobiological mechanisms and therapeutic implications. Neuroscience. 2013 Aug 29;246:199-229.
4. Emerging Risk Factors Collaboration. Diabetes mellitus, fasting glucose, and risk of cause-specific death. New England Journal Medicine, Mar 2011;364;9:328-341.
5. G. S. Hotamisligil, N. S. Shargill, and B. M. Spiegelman, “Adipose expression of tumor necrosis factor-α: direct role in obesity-linked insulin resistance,” Science, vol. 259, no. 5091, pp. 87–91, 1993.
6. Larrieu T, et al. Nutritional omega-3 modulates neuronal morphology in the prefrontal cortex along with depression-related behaviour through corticosterone secretion. Transl Psychiatry. 2014 Sep 9;4:e437.
7. Moreno-Navarrete JM et al. Circulating zonulin, a marker of intestinal permeability, is increased in association with obesity-associated insulin resistance.. PLos One 2012;7(5):e37160.
8. VanWijck K et al. Aggravation of exercise-induced intestinal injury by Ibroprofen in athletes. Med Sci Sports Exerc. 2012 Dec;44(12):2257-62.
9. Matsui H et al. The pathophysiology of non-steroidal anti-inflammatory drug (NSAID)-induced mucosal injuries in stomach and small intestine. J Clin Biochem Nutr. 2011 Mar;48(2):107-11.
10. Rebar A, et al. A Meta-Meta-Analysis of the effect of physical activity on depression and anxiety in non-clinical adult populations. Health Psychol Rev. 2015 Mar 5:1-78.