Lots of people take vitamins, minerals and other remedies they buy from health shops – so called ‘over the counter’. It is a massive industry – estimated to be worth £1.86b in the UK alone. Is this just clever marketing?
The fact remains that a normal varied diet in the UK will provide all the nutrients you need. Even vegetarians do not normally need to take supplements. One of the commonest supplements is vitamin C but I have never seen a case of scurvy – vitamin C deficiency – in my lifetime. Vitamin C does not prevent colds or infections; this has been researched for over 20 years and shown not to work. Vitamin C is water soluble and so most of it is simply eliminated in the urine, but high doses can produce excess acid in the blood causing heart and kidney problems. This can be an issue with an operation so I ask patients to stop at least a week before.
A concern for doctors is that we never actually know what the patient is taking. If you are prescribed a drug it will have gone through years of rigorous testing and the actual contents will have to be published, but supplements are not regulated in the same way and the ingredients, if listed at all, are often in the form of plants and vegetables as opposed to chemical composition. The risk of an interaction with anaesthetics or other drugs is always in the back of my mind.
If a doctor has told you to take a supplement then please do so, but always remember to bring the supplement in its original container to hospital for me to see.
So are there any other exceptions? Well, patients who are anaemic may be given iron supplements. That is fine, but I normally stop them for five days before an operation and for a couple of weeks after to avoid unpleasant constipation. A moderately low blood count is actually quite good for anaesthesia. I have written a separate blog about anaemia and iron.
Recent research suggests that both men and women lack vitamin D in the winter in the UK due to a lack of sunlight, so a single vitamin D3 tablet each day is a good idea to prevent osteoporosis or brittle bones. The recommended dose is 1000 international units – much higher does can be bought over the counter but these are for short term use only. Work at Michigan State shows that patients taking vitamin D supplements survive cancer. Very low levels can reduce fertility. It is thought that vitamin D increases the efficiency of the immune system but you need to take it for several years to actually prevent cancer.
There is some evidence folic acid, in a reasonably high dose of 800mcg a day, may reduce the risk of some cancers and some recent papers have reawakened our interest.. It is cheap and side effects are very rare unless you take about five times this dose. Research some years ago suggested an even weaker effect for selenium. I am not advising anyone to take these supplements, merely pointing you to research. And glucosamine reduces painful joints.
There are prescription and non prescription drugs which can be used to prevent as opposed to treat illness – so call prophylaxis. Statins, used to treat high levels of cholesterol in the blood, play a major role in reducing heart attacks and strokes in the normal population. Sadly there has been some poor research and a group of doctors are opposed to routine drug administration in the population but I believe the evidence is clear that if you can take statins they are worth taking. Occasionally statins can effect your liver so your doctor will measure your liver function with a blood test, normally after a month and six months. If the test is not normal we change to another statin or stop and the liver usually returns to normal. Some people have complained of muscle pain but a very clever paper from Oxford showed that this is not caused by statins and the same number of people get muscle pains when taking salt tablets.
Statins also reduce the incidence of prostate cancer in men – the connection between cancer and cardiovascular disease is a recurrent theme in this area.
The commonest cardiovascular problem is hypertension or high blood pressure, and a paper in the BMJ quantified that lowering blood pressure regardless of whether it is raised reduces strokes and ischaemic heart disease events. The greatest effect is seen with multiple drugs given in reduced doses where three such drugs give a reduction of up to 63%. Reducing the dose of each drug also reduces side effects.
My colleagues at Polypill.com now offer a single tablet with both a statin and three antihypertensive medicines. They have robust data and this is an exciting development not only for those with an increased risk of cardiovascular disease but also the population as a whole.
Aspirin also reduces cardiovascular deaths but risks bleeding from the stomach which can be fatal. Research in the general population has been unclear as to whether the benefit outweighs the risk, so although you can buy aspirin over the counter I would strongly recommend you discuss this with your GP first. Interestingly it may also protect against bowel cancer but please talk to your GP!
Another interesting development – metformin. This incredibly cheap tablet first introduced 60 years ago is used to treat type 2 diabetes. A study following patients with diabetes found those on metformin had a lower incidence of heart attacks and strokes, although diabetes, which affects the small blood vessels, would be expected to increase the risk. Then a similar result was found for cancers. Metformin is known to work by inhibiting the mTORC1 pathway within cells which is responsible for cell proliferation in cancer.
A number of large studies are underway to confirm these exciting findings whilst other groups are looking at whether the drug may be helpful for dementia. It is too early to recommend widespread use as with statins, but we know metformin is safe in non diabetics – it cannot produce a hypo or low blood sugar and is commonly used for non diabetics such as women with polycystic ovaries. So certainly one to watch.
And that brings me to GLP1 agonists – drugs such as semaglutide (Wegovy) and tirzepatide (Mounjaro). Like metformin this class was introduced to control diabetes but was quickly seen to produce dramatic weight loss in the obese and is also licensed for reducing cardiovascular disease in obese patients. Such has been the demand that the manufacturers have struggled to supply and many people have used it as a lifestyle drug, ignorant of serious gastrointestinal risks, pancreatitis, gall bladder issues and hypoglycaemia.
Currently it should only be used under medical supervision for the truly obese (BMI over 30 kg/m2) or diabetics. However there is interest in these drugs in relation to cancer and possibly dementia along the same lines as metformin. Over the next few years we will see tablet preparations, the price will fall and our knowledge will increase such that GLP1 agonists may be recommended prophylactically. Even if not, the ability to fight back against obesity (the incidence of obesity in the US fell for the first time in 2023) offers massive societal savings in terms of falls in joint replacement, intensive care, unemployment and disability.