Low blood pressure and postural hypotension

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During evolution a stage was arrived at when monkeys and apes decided to stand up. They also liked hanging upside down in trees! This presented a terrible problem for the circulatory system because unless blood pressure was kept constant, some parts of the body would get too much blood, some too little. The only way this constancy of blood pressure could be achieved was by allowing the brain to control blood supply. This control is achieved by nerves connecting to muscles in blood vessel walls telling them either to contract or relax. Contracting would reduce blood supply, relaxing would increase it. So when the ape stood up suddenly, the arteries to the leg and gut would contract a bit, the arteries to the head and arms would relax a bit. If this did not happen, the ape would fall over in a dead faint as blood followed gravity and pooled in the legs.

Control of blood pressure is done without us having to think about it - thank goodness! This automatic control is carried out by the autonomic nervous system. If the autonomic nervous system is damaged by pesticides, chemicals, free radicals or nutrient deficiencies then postural hypotension is one result.

Symptoms of postural hypotension

  • You may faint if you don't sit down (or lie down) quickly. If you don't actually faint, blood supply to the brain is reduced resulting in feeling dizzy, "spaced out" or "not with it".
  • Postural hypotension usually occurs when you stand up. It is worse if you are hot because blood is already diverted to skin and so it often happens to people when they are getting out of bed.
  • There are some funny reflexes which can result in postural hypotension for example having a pee. This may explain why some men faint in the night when nipping out for a pee.
  • Any drug for blood pressure could worsen a tendency to postural hypotension.


  • Try to identify and avoid obvious causes - think about pesticides, chemicals, free radicals or nutrient deficiencies. Diabetics may get autonomic neuropathy because high blood sugar levels damage nerves.
  • Give your body time to adjust - don't jump up too quickly.
  • Work the muscles of your legs for a few seconds before standing up - this prevent blood pooling in legs as the muscles squeeze the blood out of the veins back to the heart.
  • I would treat postural hypotension as a sort of peripheral neuropathy and use high dose B vitamins and possibly vitamin B12 injections to encourage the nerves to heal and repair. I would also check DHEA levels on the grounds that this encourages repair of tissues. See DHEA (saliva) single and B vitamins - functional blood profile
  • Postural hypotension could be caused simply by low cardiac output. See Low cardiac output state. It is much easier for the heart to pump blood on the flat (lying down) than up and downs hills (standing up). Indeed we all feel more comfortable lying down or sitting rather than standing. In severe cases of chronic fatigue syndrome the heart is in a low output state, perhaps sufficiently so that it cannot pump enough blood round when standing. It can maintain blood pressure for a certain time, but then becomes fatigued and so the blood pressure falls. Clinically this is called Postural orthostatic tachycardia syndrome or POTs. The treatment of course is to treat the mitochondrial problem. See CFS - The Central Cause: Mitochondrial Failure.

Useful Website

Please see POTS UK Charity Website for lots of useful ideas and information.

Further thoughts

Please see Postural orthostatic tachycardia syndrome (POTS) and the vagus nerve for further thoughts on POTS.

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