We’re all being told that climate change is a critical concern throughout the world, and as sprng moves into summer soon in my part of the world, and the temperature heats up, I know how tough the outside temperature may be for those of you struggling with hot flushes and night sweats.
Many of my clients in the northern parts of Australia relate to this, I know!
Hot flushes, night sweats and menopause insomnia are all related physiological events. So, when it comes to the regulation of our body temperature in middle-age, and how we respond to environmental heat and heat loss from our body, women differ from men.
I bet that many of you, like me, never gave your heat regulation a thought prior to menopause.
But the skin – our largest organ – is replete with oestrogen receptors.
Not only does this mean that these receptors struggle to find oestrogen to attach to them as oestrogen levels naturally decline during the menopause transition, but because the skin is also replete with sweat glands, there are changes to these as well.
Which is why, when it comes to regulation of heat in menopause, we can’t compare ourselves to males.
Women have a greater subcutaneous fat content compared to males and fat isn’t a wonderful conductor of heat. Hence if we put on weight during menopause, hot flushes/ flashes may increase.
When it comes to heat regulation in the female body though, it isn’t always about our sweat glands and how we get rid of heat. There are other factors going on too.
And this is why, I want you to know about the curious connection between your circadian rhythm, body heat and hot flushes and why temperature regulation changes with age.
Why you have to sleep to beat the heat!
When I first began to have hot flushes and high blood pressure as I moved into my early 50s, nobody mentioned my lack of sleep or circadian rhythm. The aches and pains arrived not long afterwards as did my feelings of fatigue.
These days I know why those endless expensive supplements and HRT weren’t helping to reduce my body temperature either.
Menopause hormonal changes affect the circadian cycle of the body, which in turn, disrupts temperature regulation, which in turn, disrupts the cardiovascular and immune health of women. It is indeed a ‘tangled threesome!’. [Coiffard, Diallo et al, 2021].
‘In mammals, including humans, the body temperature displays a strict circadian rhythm and has to be maintained within a narrow range to allow optimal physiological functions.
There is nowadays growing evidence on the role of the temperature circadian rhythm on the expression of the molecular clock. The Circadian Rhythm Body Temperature (CRBT) participates in the phase coordination of circadian timekeepers in peripheral tissues, thus guaranteeing the proper functioning of the immune system’.
[Coiffard, Diallo et al, 2021]
Your circadian rhythm (the regulation of your body’s 24 hour clock), strongly influences your human biology and disease states.
Almost all of the functions of the human body show circadian pattern that is under control of biological clocks. Biological clocks differ from the circadian clock. In humans, nearly every tissue and organ has its own circadian rhythm, called a biological clock, and collectively they are tuned to the daily cycle of day and night (the circadian rhythm).
From our blood pressure to our immune health, to our temperature control, to liver health and gut function, our circadian clock matters.
Menopause hormonal changes mess up these biological clocks when you aren’t sleeping, or if you do a lot of long-haul flying. Shift work also messes up your biological clocks and your circadian rhythm.
This may be why, if your HRT isn’t working any more, nor are your various supplements to help your hot flushes, especially if you are in post-menopause, then you might want to have a little focus on restoring your circadian rhythm. Yes, in menopause and beyond, it’s that important for your healthy ageing and your weight management too.
Every major organ works to your circadian night/day cycle.
The image above of Christine, is a powerful example of how focusing on your sleep matters to blood pressure. She is a nurse, who has worked shifts for many years and didn’t understand the vascular (blood vessel) changes occuring during her menopause transition.
Circadian type blood pressure rhythm refers to the daily variation of BP that is generally higher during the day than at night – it’s especially high in the early evening hours when you are getting home from work, or doing all the jobs that you need to get done. If you feel over-heated in the evening, then this is when both blood pressure and temperature increases as part of a normal circadian pattern.
Between 6pm – 9pm is when your blood pressure is high and your body temperature at its highest as well.
For women joining me on my menopause symptom reduction programmes, I suggest new evening routines and foods which are evidenced to help to lower their blood pressure, especially after a busy, stressful day at work.
Physiological body temperature is approximately 37˚C in healthy humans with approximately, a 1˚ variation within the circadian cycle.
If you want to manage your hot flushes in menopause and you want to reduce your blood pressure and improve your immune health, then you need to sort out your circadian cycle as much as you can. The effects of temperature variability on immune function can’t be underestimated. A higher body temperature makes us more vulnerable to infection and immune disorders. (Coiffard et al., 2021).
It’s why the very first module I have in the MyMT™ programmes is simply called ‘Sleep All Night’ – it’s that important to your hot flushes and blood pressure management.
Factors disrupting your circadian rhythm and biological clocks during menopause.
- The type, timing and amount of food you eat. Women on my programmes know that high protein diets increase heat production in the body. Protein has the highest thermo-genic (heat generating) effect. Many daily protein calculations are derived from sports nutrition studies, so I change this calculation to reflect women’s health and ageing research. Furthermore, our body needs glucose from starch carbohydrates and metabolism of this is better in the morning. Numerous women get off all carbohydrates and go on high-fat Keto diets, but there are certain carbohydrates that we need for our cardiac health and circadian cycle.
- The level of inflammation in your body going into menopause (those of you with high stress levels or you are doing lots of exercise, please take note!).
- How efficiently you can dissipate (remove) the heat from your skin as sweat. This emerges as a problem in women during menopause, as skin (our largest organ), changes in response to the decline in oestrogen.
- Whether you are a shift-worker. Night workers display significant circadian rhythm abnormalities, including disruption of the body temperature. I have lots of shift workers on my programmes and I work with them to put in place strategies that help them prepare for sleeping in the day.
- Whether you work late into the night and go to bed late.
- The amount of physical exercise or activity you are doing as well as how aerobically fit you are. One of the things I discuss in the Rebuild My Fitness programme is that how quickly your heart rate returns to normal after exercise is now seen as an important marker, not only as a measurement of aerobic fitness, but also as a biomarker of the circadian management of blood pressure. [Okutucu et al., 2011].
Get in Sync!
The regulation of your body temperature is synchronized by your body clock and this is regulated by light reaching your tiny pineal gland every morning.
This is why our brain needs to register a contrast between day and night – to ensure that our body experiences a reproducible rhythm in behaviour, waking in the morning and sleeping in the evening.
This helps our brain to ‘rest’ and ‘wake’ which in turn helps to regulate the function of other circadian clocks on many peripheral tissues, such as the liver, heart, arteries, skin and lymphocytes.
For women going into menopause and beyond, this is crucial to know, because every one of these regions in the body are declining in oestrogen and as such, our menopause transition affects the function of other organs in our body.
Hence, as women on my 12 week coaching programmes discover, if we sort out our circadian rhythm changes during menopause, then we sort out many of our other symptoms too.
I talk about this in my online Masterclass on Menopause and give you some solutions in this wonderful educational module for you as well. Have a listen to the video below when you can as I explain what’s in my 2 hr Masterclass – and yes, because I’ve pre-recorded it, you can ‘pause’ me anytime you like as well.
Learn about the world class MyMT™ Programs.
Can I help you with your symptoms or your weight?
If you are struggling with your mid-life weight, health or symptoms, then come on board into my 12 week online programs. MyMT™ programs are normally available for NZ$399 each for 3 months and you work with me to problem-solve too. Please do check out the MyMT website or subscribe to our newsletter to be alerted to any promotional offers.
Or as a starting point, you can purchase my online Masterclass on Menopause. This is only NZ$15 (approx. AUS$14, US$9 or UK£7.50). I hope you can join me in this powerful 2 hour webinar.
The great news is that now you can watch it anytime, anywhere and even pause it whenever you like and go and make yourself a cuppa too.
References:
Coiffard, B., Diallo, A. B., Mezouar, S., Leone, M., & Mege, J. L. (2021). A Tangled Threesome: Circadian Rhythm, Body Temperature Variations, and the Immune System. Biology, 10(1), 65. https://doi.org/10.3390/biology10010065
Kaciuba-Uscilko, H., Grucza, R. (2001). Gender differences in thermoregulation. Current Opinion in Clinical Nutrition and Metabolic Care, 4(6), 533-536
Jehan, S., Giardin, J-L, Auguste, E., et al (2017). Sleep, Melatonin and the Menopausal Transition: What are the links? Sleep Science, 10(1): 11-18.
Molnar, G. (1975). Body temperatures during menopausal hot flashes. J. of Applied Physiology, 38.3.499
Okutucu, S. & Karakulak, U. & Kabakci, G. (2011). Circadian blood pressure pattern and cardiac autonomic functions: Different aspects of same pathophysiology. The Anatolian Journal of Cardiology. 11. 168-73. 10.5152/akd.2011.031.
Reinke H. & Asher G. (2017). Circadian clock control of liver metabolic functions. Gastroenterology, 150: 574–580.
Rizzi, M. et al. (2016). Sleep Disorders in Fibromyalgia Syndrome. Journal of Pain Relief, 5:2, 1-5
Sharma, S. & Kavuru, M. (2010). Sleep and Metabolism: An Overview. Int. Journal of Endocrinology, Article ID 270832, 1-12.
