Blood sugar and carbohydrate imbalances
What we eat and when we eat it is essential to ensure proper blood sugar management, which in turn is essential for hormonal balance and mental health Penckofer, S., Quinn, L., Byrn, M., Ferrans, C., Miller, M. and Strange, P. (2012). Does glycemic variability impact mood and quality of life? [online] Diabetes Technology & Therapeutics, 14 (4), pp. 303–310. Available at: https://www.ncbi.nlm.nih.gov/pubmed/22324383 [accessed 24 Aug. 2017]..
Carbohydrates, which turn into glucose in the blood, are essential for the functioning of the body and the brain, as glucose is the main source of fuel for the brain Berg, J., Tymoczko, J., Stryer, L. (2002). Biochemistry. 5th ed. [online] New York: W H Freeman. Available at: http://www.ncbi.nlm.nih.gov/books/NBK22436/ [accessed 24 Aug. 2017].
The brain needs glucose to function. And it needs a lot of it, in a steady supply:
- In a resting state, the brain consumes up to 60% of our daily glucose intake Berg, J., Tymoczko, J., Stryer, L. (2002). Biochemistry. 5th [online] New York: W H Freeman. Available at: http://www.ncbi.nlm.nih.gov/books/NBK22436/ [accessed 24 Aug. 2017].
- The brain particularly likes a steady and sustainable release of sugar, and works best when there is constant access to a source of glucose – not too high, not too low
- Glucose lights up the reward circuits of the brain, and prompts the release of feel good chemicals such as dopamine, serotonin, endorphins and endocannabinoid Holland, J. (2015). Moody Bitches. New York: Penguin, p. 165.
Mergenthaler, P., Lindauer, U., Dienel, G. and Meisel, A. (2013). Sugar for the brain: the role of glucose in physiological and pathological brain function. [online] Trends in Neurosciences, 36 (10), pp. 587–597. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3900881/ [accessed 24 Aug. 2017].
Effects of sugar consumption on the brain and moods:
- Consuming sugar can create temporary feelings of bliss
- Consuming sugar can give you temporary better impulse control
- Controlled activities that rely on executive functions (such as attention, reasoning, planning, self control) which override urges, emotions and automatic responses
- Executive functions, unlike other cognitive functions, seem highly susceptible to glucose fluctuations
- Evidence shows that self-control failure may be more likely when glucose is low, or glucose transport to the brain from the body is low
- Some studies have linked criminal behaviour to decreased glucose processing in the brain Gailliot, M., Baumeister, R., DeWall, C., Maner, J., Plant, E., Tice, D., Brewer, L. and Schmeichel, B. (2007). Self-control relies on glucose as a limited energy source: willpower is more than a metaphor. [online] Journal of Personality and Social Psychology, 92 (2), pp. 325-36. Available at: https://www.ncbi.nlm.nih.gov/pubmed/17279852 [accessed 24 Aug. 2017].
- Self-control relies on glucose as a limited energy source: willpower is more than a metaphor
- Consuming sugar can make you feel less sensitive to pain DesMaisons, K. (2004). Little Sugar Addicts: End the Mood Swings, Meltdowns, Tantrums, and Low Self-Esteem in Your Child Today. New York: Three Rivers Press, p. 21.
- However, after a sugar high, your body compensates by removing sugar from the blood, resulting in a crash in blood sugar and a crash in serotonin and beta endorphins which then can make you feel down DesMaisons, K. (2004). Little Sugar Addicts: End the Mood Swings, Meltdowns, Tantrums, and Low Self-Esteem in Your Child Today. New York: Three Rivers Press, p. 19.
- Therefore it is important to consume sugar in the form of complex carbohydrates (beans, pulses, whole grains, starchy vegetables, etc.) instead of refined carbohydrates (processed, refined sugars and flours), as they take longer to digest and allow for balanced blood sugar and a steady release of glucose for the brain Sathyanarayana Rao, T., Asha, M., Ramesh, B. and Jagannatha Rao, K. (2008). Understanding nutrition, depression and mental illnesses. [online] Indian Journal of Psychiatry, 50 (2), pp.77-82. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2738337/ [accessed 24 Aug. 2017].
Blood sugar imbalances and their effects on mental health
Problems happen when blood sugar levels fluctuate wildly and often, which can create hormone imbalances, due in part to the correlation between blood sugar levels and levels of stress hormones cortisol and adrenaline, as well as levels of insulin. These hormone imbalances can lead to imbalances in other hormones and neurotransmitters, and lead to mental health symptoms.
Both high blood sugar and low blood sugar can cause the following mental health symptoms:
- High blood sugar is associated with negative mood, tension, anger, and sadness
- Low blood sugar is associated with nervousness, irritability, fatigue and attention issues
- Individuals with type 1 or 2 diabetes are at increased risk for depression, anxiety and eating disorders
Penckofer, S., Quinn, L., Byrn, M., Ferrans, C., Miller, M. and Strange, P. (2012). Does glycemic variability impact mood and quality of life? [online] Diabetes Technology & Therapeutics, 14 (4), pp. 303–310. Available at: https://www.ncbi.nlm.nih.gov/pubmed/22324383 [accessed 24 Aug. 2017].
While the brain needs glucose to function, too much glucose can be toxic for nerve cells and damage them,
causing inflammation in the brain Tomlinson, D. and Gardiner, N. (2008). Glucose neurotoxicity. [online] Nature Reviews Neuroscience, 9 (1), pp. 36–45. Available at: https://www.ncbi.nlm.nih.gov/pubmed/18094705 [accessed 24 Aug. 2017]..
If you eat a diet high in fast assimilating sugars, such as refined carbohydrates and foods with a high glycemic index (the glycemic index measures how quickly and how much a food raises blood glucose levels) which cause a rapid rise in blood sugar levels, especially when you eat these alone without protein or fat, you may get a sugar high, which may feel great at first, due to the glucose effect on the reward chemicals in the brain, but then can produce mental health symptoms Sathyanarayana Rao, T., Asha, M., Ramesh, B. and Jagannatha Rao, K. (2008). Understanding nutrition, depression and mental illnesses. [online] Indian Journal of Psychiatry, 50 (2), pp. 77-82. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2738337/ [accessed 24 Aug. 2017].
Jakubowicz, D. and Froy, O. (2013). Biochemical and metabolic mechanisms by which dietary whey protein may combat obesity and Type 2 diabetes. [online] The Journal of Nutritional Biochemistry, 24 (1), pp. 1–5. Available at: https://www.ncbi.nlm.nih.gov/pubmed/22995389 [accessed 24 Aug. 2017]. such as:
- Poor memory
- Poor concentration and attention
- Hyperactivity (ADD and ADHD)
Lake, J. (2009). Integrative Mental Health Care. New York: W.W. Norton & Co., p. 196., Holford, P. (2004). Patrick Holford’s New Optimum Nutrition Bible. London: Piatkus, p. 89.
Usually, after a period of high blood sugar caused by quick-release sugars such as refined carbohydrates on their own, your blood sugar plummets, which can also happen if you skip meals. Then you can suffer from mental health related symptoms of low blood sugar.
As mentioned above, the brain needs a large amount of the body’s glucose to function (60%) Berg, J., Tymoczko, J., Stryer, L. (2002). Biochemistry. 5th ed. [online] New York: W H Freeman. Available at: http://www.ncbi.nlm.nih.gov/books/NBK22436/ [accessed 24 Aug. 2017].. Lack of glucose to the brain can lead to the following symptoms:
- Brain fog and fuzzy thinking
- Poor concentration and attention
- Poor memory
Holford, P. (2004). Patrick Holford’s New Optimum Nutrition Bible. London: Piatkus, p. 17, pp. 87-8.
If you have sugar sensitivity, you will be more susceptible to blood sugar fluctuations.
Symptoms of sugar sensitivity related to mental health include:
- Being easily stressed
- Anger and irritability
- Cravings/addiction for sugary food
DesMaisons, K. (2004). Little Sugar Addicts: End the Mood Swings, Meltdowns, Tantrums, and Low Self-Esteem in Your Child Today. New York: Three Rivers Press, p. 28., Talbott, S. (2007). The Cortisol Connection. Alameda, CA: Hunter House, p. 51.
People with sugar sensitivity tend to have low base levels of the neurotransmitter serotonin, and low beta-endorphins. They tend to crave sugar to make themselves feel better, because the consumption of sugar has the following neurochemical effects:
- Increases dopamine, the pleasure and motivation neurotransmitter, and therefore can be addictive
- Can help the absorption of tryptophan and its conversion to serotonin
- Increases endorphins in the brain, particularly in the nucleus accumbens (referred to as the hedonic “hot spot”)
Fortuna, J. (2012). The obesity epidemic and food addiction: clinical similarities to drug dependence. [online] Journal of Psychoactive Drugs, 44 (1), pp. 56–63. Available at: https://www.ncbi.nlm.nih.gov/pubmed/22641965 [accessed 24 Aug. 2017].
However a while after consuming sugar, their blood sugar crashes, and they will crave more sugar to compensate for the loss of feel good chemicals. They will seek to eat more sugar, and the cycle repeats DesMaisons, K. (2004). Little Sugar Addicts: End the Mood Swings, Meltdowns, Tantrums, and Low Self-Esteem in Your Child Today. New York: Three Rivers Press, pp. 18-22..
Contributors to blood sugar imbalances
There are many factors which can contribute to blood sugar imbalances:
Diets high in refined carbohydrates such as white sugar, white flour, high glycemic index foods, can cause blood sugar imbalances:
- Through processing, complex carbohydrates are turned into simple ones which are essentially pre-digested
- They are fast-releasing sources of energy and have a high glycemic load prompting a rapid increase in blood sugar which usually leads to a subsequent rapid fall in blood sugar Talbott, S. (2007). The Cortisol Connection. Alameda, CA: Hunter House, p. 19.
- The problem is that we often crave rapid sugar in the form of junk food, as it makes us feel better temporarily, giving us quick energy, and lighting up our reward circuits
- However the effects don’t last, and the crash after eating highly refined carbohydrates can be very unpleasant
- Spikes and slumps in blood sugar from the consumption of refined carbohydrates can lead to mood swings, low energy, and don’t allow for the steady release of energy which your brain requires Talbott, S. (2007). The Cortisol Connection. Alameda, CA: Hunter House, p. 151.
As well as diets low in proteins and fats:
- Consuming protein and fats with carbohydrates slow down the digestion process and ensure a more steady and even release of blood sugar, which is better for the brain
- Diets low in proteins and fats can lead to more unstable blood sugar levels
Fasting, dieting or skipping meals can lead to unstable blood sugar levels.
Eating refined carbohydrates rather than complex ones can lead to blood sugar imbalances.
Human tolerance to sugar starts in the womb. Babies of mothers who have diabetes, start their life with a genetic predisposition towards insulin resistance and can subsequently pass these genes on to the next generation.
Genetic factors also play a role how people perceive and tolerate the taste of sweetness. Those genetically more sensitive to sweet tastes can eat less sugar to achieve the same perception of sweetness, while those genetically less sensitive to sweet tastes may need to eat more sugar to achieve the same perception of sweetness Taubes, Gary, (2016). The Case Against Sugar. London, UK: Portobello Books
When carbohydrates cause an increase in blood sugar, the pancreas releases insulin to mop up the glucose in the blood and carry it out of the bloodstream, into the cells.
However, when blood sugar is chronically high due to a diet high in sugar and refined foods, the pancreas keeps pumping out more and more insulin, which then has the effect of numbing our cells’ sensitivity to insulin, i.e., the cells refuse entry to insulin. This can lead to a condition called “insulin resistance” which is a precursor to diabetes.
Insulin resistance means that we are no longer able to adequately regulate our blood sugar, which can remain chronically high as a result.
Chronically high blood sugar and insulin resistance can then lead to inflammation, throw other hormones and neurotransmitters out of balance, and lead to a rapid degeneration of the brain, mood and mental health Kharrazian, D. (2013). Why Isn’t My Brain Working? CA: Elephant Press, pp. 186-7..
There is a correlation between adrenal or HPA dysfunction, and blood sugar imbalance, as well as sugar sensitivity:
- Hyperactivity of the HPA (hypothalamic-pituitary-adrenal) axis can contribute to hyperinsulinemia Miranda, R., Torrezan, R., de Oliveira, J., Barella, L., da Silva Franco, C., Lisboa, P. and Moura, E. (2016). HPA-axis and vagus nervous function are involved in impaired insulin secretion of MSG-obese rats. [online] Journal of Endocrinology, 230 (1), pp. 27-38. Available at: https://www.ncbi.nlm.nih.gov/pubmed/27113853 [accessed 24 Aug. 2017].
- A condition in which there are excess levels of insulin circulating in the blood relative to the level of glucose, often mistaken for diabetes or hyperglycaemia
- Its symptoms include
- Weight gain
- Sugar cravings
- Intense and frequent hunger
- Difficulty concentrating
- Anxiety and panic(2017). Hyperinsulinemia. [online] Diabetes. Available at: http://www.diabetes.co.uk/hyperinsulinemia.html [accessed 27 Oct. 2017].
- Conversely, blood sugar dysregulation can impact insulin and cortisol which then has a disruptive impact on the HPA axis
- A primary role of cortisol is to regulate blood sugar availability
- Glucose is needed for ATP production (ATP is the fundamental energy unit of the cell)
- If blood sugar drops, cortisol is secreted to bring it back up to a normal range, in order to provide for energy production
- Hypothyroidism tends to co-exist with type 1 and 2 diabetes
- Hypothyroidism is linked with various hormonal biochemical and nervous abnormalities which may contribute to hypoglycaemia
- Hypothyroidism is linked with low growth hormone and cortisol responses to insulin-induced hypoglycaemia and this prevents adequate counter regulatory protection Kalra, S., Unnikrishnan, A. and Sahay, R. (2017). The hypoglycemic side of hypothyroidism. Indian Journal of Endocrinology and Metabolism, 18 (1), pp. 1-3. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3968713/ [accessed 24 Aug. 2017].
Having an infection, being ill or very stressed can result in blood sugar imbalances:
- Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, and elevates cortisol
- Elevated cortisol increases glucose production within liver cells which increases blood glucose
- Elevated cortisol inhibits insulin secretion from pancreatic beta cells as well as muscles
- This can lead to impaired glucose tolerance and insulin resistance
Almadi, T., Cathers, I. and Chow, C. (2013). Associations among work‐related stress, cortisol, inflammation, and metabolic syndrome. [online] Psychophysiology, 50 (9), pp. 821–830. Available at: https://www.ncbi.nlm.nih.gov/pubmed/23758414 [accessed 24 Aug. 2017].