Can thermotherapy help dementia? That question was asked recently by Australian and English scientists in their 2020 review, Could Heat Therapy be an Effective Treatment for Alzheimer’s and Parkinson’s Disease?1 They look at the complex physiology behind these diseases and the effects that heat therapy has on the physiology. Despite not knowing exactly how it works, and despite only one study associating thermotherapy with decreased dementia, they say “the emerging evidence is compelling”.

They referred to a study2 looking at over 3,000 middle-aged Finnish men. The study found that those who reported having a sauna 4 or more times per week developed 66% less dementia, and 65% less Alzheimer’s, than men who only used the sauna once a week over the 20 years they were studied.

Just recently another paper3, from Finland, has come out. The researchers studied nearly 14,000 men and women for 39 years. Those people who had a sauna 3-4 days per week had nearly 20% less dementia than those who used the sauna once or less per week.

What do the studies show?

Taken together, these studies show that sauna does reduce the risk of dementia but the amount that it reduces it by decreases the older people get. It suggests to me that sauna is not necessarily preventing dementia, instead, it pushes it back for maybe 10 years. This seems to be supported by the results at the 20-year follow-up for the second study, here, more frequent sauna bathers had 53% less dementia. Which is much closer to the first study’s results.

These studies are looking at the association between dementia and thermotherapy, that’s prevention, not treatment, so it is impossible to say whether it will work for people with dementia. What I can say is that I have seen people with cognitive decline make large improvements (with memory returning to the normal range) in lifestyle-change programs.

Since my father died of vascular dementia I have had a strong interest in this area and even developed a dementia prevention program using lifestyle change. I based it on work by Drs Sherzai directors of Loma Linda University’s Brain Health and Alzheimer’s Prevention Program in the US. They say that with lifestyle change it is possible to reduce the risk of Alzheimer’s by 90%.

I call my program, 5 Good Years because I believe that, looking at all the evidence, it is probably possible to push the disease back by 5 years. And that was without the thermotherapy! What I’m learning is that thermotherapy gives people a real head start on lifestyle change and the benefits add up more quickly than lifestyle change alone.

Why does sauna prevent dementia?

No-one knows yet. But there are several proposed mechanisms.1,3:

  1. In dementia, misfolded proteins accumulate in the brain. The sauna makes the body produce heat shock proteins which stop proteins being misfolded.
  2. Decreased blood supply, poor blood-vessel health, and high blood pressure are associated with dementia. Sauna improves the blood supply and the health of blood vessel walls, as well as decreasing high blood pressure.
  3. Brain inflammation is found in most dementias. Sauna reduces inflammation.
  4. Type 2 diabetes is a risk factor for Alzheimer’s disease. Sauna may help with the control of blood sugar levels and glucose intolerance.
  5. Poor sleep is associated with dementia. Sauna may improve sleep quality.
  6. Chronic stress is a risk factor for dementia. Sauna use is relaxing for most people but the change in stress levels has not been closely studied.

I’m not sure what would happen for someone who already has a diagnosis of dementia but if you have diagnosed Mild Cognitive Impairment or you are just worried about your brain health (Subjective Cognitive Decline), my experience leads me to think that lifestyle change and thermotherapy will probably make some positive difference.

Talk to your doctor

You will need to check with your GP about the contraindications to thermotherapy. These become more important as we get older, especially if you have a diagnosis of dementia or mild cognitive impairment.

The questions you ask yourself to work out if you have subjective cognitive decline are:

  1. Is my memory (or general thinking) worse than most people my age?
  2. Has my memory or thinking been steadily declining for the last year or so?

If you answered “Yes” to either, or both, of these questions, you may have subjective cognitive impairment. I have seen very quick improvements in these areas with lifestyle change. Thermotherapy may accelerate these changes.

So can thermotherapy help your dementia? The answer is unclear, but there are good signs that it may.

Let’s see.

    1. Hunt AP, Minett GM, Gibson OR, Kerr GK, Stewart IB. Could Heat Therapy Be an Effective Treatment for Alzheimer’s and Parkinson’s Diseases? A Narrative Review. Frontiers in Physiology. 2020. doi:10.3389/fphys.2019.01556
    2. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer’s disease in middle-aged Finnish men. Age Ageing. 2017;46: 245–249.
    3. Knekt P, Järvinen R, Rissanen H, Heliövaara M, Aromaa A. Does sauna bathing protect against dementia? Preventive Medicine Reports. 2020. p. 101221. doi:10.1016/j.pmedr.2020.101221

Bruce ThompsonAUTHOR

BAppSc-Physiotherapy, Sydney University 1978

Bruce Thompson is a qualified Physiotherapist who has been using and teaching hydrotherapy for over 30 years.

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