Why is cortisol so important?
There have been a number of questions recently about cortisol. This week, Dr Libby has grouped a number of these together.
What is the role of cortisol in the body? Why is it important? I’ve been hearing a lot about it lately. Thanks, Joan.
Hi Joan. Cortisol is a powerful anti-inflammatory agent in the body, as well as playing a role in immune system and blood glucose regulation. It is also one of our stress hormones. The human body makes two main stress hormones. They are adrenalin and cortisol. Adrenalin drives the short-term stress response which in the past signalled to the body that our life was in danger. But today, we make adrenalin primarily due to caffeine consumption and our perception of pressure and urgency. Because these latter two scenarios are constant and relentless for many people, adrenalin never switches off. This leads to (among many other things) chronic inflammation. The body can’t withstand this so excessive amounts of cortisol are then made.
Cortisol is our chronic stress hormone. In other words, we tend to make too much of it when we are stressed for a long time. Historically, the only long-term stresses humans had were floods, famines and wars; all scenarios where food may have been scarce.
Today, our long-term stress tends to come from relationship or financial worries, or health or weight concerns. However, because cortisol was designed to save your life when food was scarce, even though food may be abundant for you today, cortisol sends a message to every cell in your body that your metabolism needs to be slowed down so that those precious fat stores can keep you going until food returns.
Can you explain the link between stress, cortisol and weight gain? Are they related? Kind regards, Maude
Hi Maude. If we remember that we are completely geared for survival and that cortisol tells every cell of the body that food is scarce, another of its roles is to slow down your metabolic rate. It does this by driving catabolism – breaking your muscles down. Muscles use more energy than body fat so the less muscle mass you have, the slower your metabolic rate will be.
A slower metabolism leads you to burn body fat for energy far more slowly then you have in the past, as cortisol is designed to make sure that you survive this perceived period of famine.
How does taking time to do activities that lower stress, such as nature walking, help lower cortisol and thus assist with weight loss? Thanks, Lyndall
Hi Lyndall. Managing stress involves different strategies for different people.
However, common threads include a reduction in caffeine consumption (caffeine drives adrenalin production, our shortterm stress hormone), incorporating a breath-focused practice such as yoga, meditation, tai chi or Pilates, as diaphragmatic breathing activates the calming arm of the nervous system, known as the parasympathetic nervous system (PNS).
Dr Libby has a new range of food-based nutritional supplements. Visit www.bioblends.co.nz for more information. See drlibby.com for her blog.
Dr Libby is a nutritional biochemist, best-selling author and speaker. The advice contained in this column is not intended to be a substitute for direct, personalised advice from a health professional.
Cortisol is a long-term stress hormone which we used to make when food was scarce. Today stresses tend to be financial or relationship worries which can last for a long time.