A cheap dietary pill used to soothe the agony of arthritis can slash the risk of a heart attack or stroke by more than a fifth, according to research.
A study of almost half a million people found those who used glucosamine regularly were up to 22 per cent less likely to die from cardiovascular disease (CVD).
Researchers believe the supplement slashes levels of C-reactive protein (CRP) – a chemical associated with inflammation and heart attacks.
But critics doubt the findings, saying the dose of glucosamine consumed was not specified and it wasn’t clear if participants were taking other supplements.
Glucosamine is a supplement consumed by millions of people around the world to ease the misery of joint pain.
Glucosamine use slashed the risk of cardiovascular disease by more than a fifth in a study of almost 500,000 Brits
Animal studies have found that it can both delay the breakdown of and repair damaged cartilage.
The compound is produced naturally by the body in cartilage between the joints.
But evidence on whether it works in humans is mixed, with many studies showing little or no effect on pain relief or joint function.
Researchers from Tulane University in New Orleans, Louisiana, followed 466,039 male and female Britons without CVD for an average of seven years.
Using death certificates and hospital records they found glucosamine was associated with a 15 per cent lower risk of CVD events.
The findings also showed that coronary heart disease (CHD), strokes and deaths from CVD were reduced by between nine and 22 per cent.
These associations remained after taking account of traditional risk factors, including age, sex, weight (BMI), ethnicity, lifestyle, diet, medication and other supplement use.
Overall, almost one in five participants – 19.3 per cent – reported glucosamine use at the start of the study.
Lead researcher Professor Lu Qi said: ‘Several potential mechanisms could explain the observed protective relation between glucosamine use and CVD diseases.
Regular use of glucosamine was associated with a statistically significant reduction in CRP concentrations, which is a marker for systemic inflammation.
‘Animal studies also reported that the anti-inflammatory properties of glucosamine might have a preventive role in the pathophysiology of CVD.
‘In addition, a previous study found that glucosamine could mimic a low carbohydrate diet by decreasing glycolysis and increasing amino acid catabolism in mice; therefore, glucosamine has been treated as an energy restriction mimetic agent.
‘Other mechanisms might also be involved, and future investigations are needed to explore the functional roles of glucosamine in cardiovascular health.’
The new findings, published in The British Medical Journal, are based on an analysis of data from the UK Biobank study that contain the health records of hundreds of thousands of people.
During the course of the follow-up period there were 10,204 CVD incidents, 3,060 CVD deaths, 5,745 coronary heart disease events, and 3,263 strokes.
WHAT IS GLUCOSAMINE?
Glucosamine is a supplement consumed by millions of people around the world to ease the misery of joint pain and arthritis.
The compound – produced naturally by the body in cartilage between the joints – is believed to reduce inflammation.
Natural sources include the ends of chicken bones and crustacean shells.
Supplements can be bought in high street retailers such as Holland and Barrett for as little as £17 for 60 tablets.
Animal studies have found that glucosamine can both delay the breakdown of and repair damaged cartilage.
But evidence on whether they work on humans is mixed.
Source: Versus Arthritis
Participants were enrolled from 2006 to 2010 and were followed up to 2016.
Dr Louisa Lam, deputy dean of the school of nursing and healthcare professions at Federation University in Australia, said: ‘There is so much controversy around the effects of glucosamine and vitamin supplements in general, and I do have my doubts about this analysis.
‘There is lots of research evidence that supports my doubt. My view is that the study has a very large sample, and with large samples like that, it is easy to find some statistical significance in ‘things’ the researchers want.
‘I would really like to see if there is an association with other supplements and CVD events or death.
‘The authors should provide information on other supplements as comparisons. Also, a Yes and No answer on the use of Glucosamine is insufficient.
‘We need dose and length information. I have my doubts about the reported result in relation to the link between glucosamine supplements and lower risks of CVD events.’
Professor Naveed Sattar at the University of Glasgow, said only a clinical trial could determine whether the supplement lowers the risk of heart disease.
He added: ‘Whilst the authors have done a careful job of analysing the link between glucosamine intake and cardiovascular outcomes in a big dataset, only a trial can determine whether there is any truth to the lower observed risk.
‘Observational studies can only ever generate new ideas to test. They cannot prove a causal link since some biases are impossible to overcome and it may well be those who take glucosamine regularly have healthy lifestyles in ways that are not fully captured by measured data.
‘Many other supplements have not proven benefits in trials even when observational data suggested there may be health benefits.
‘Some supplements have even been shown to cause harm in trials. So, for now, I would not rush to buy glucosamine to lessen my heart risks when there are many other cost-effective proven ways to do so.’
The findings come after the British Heart Foundation (BHF) announced that heart disease-related deaths had gone up for the first time in 50 years.
Although the overall death rate is still improving, fatalities in the under-75 age group have been climbing since 2015.
The worrying trend follows decades of progress which has seen premature death rates plummet since the 1960s.
Figures show 42,384 people in the UK died from conditions including heart attack and stroke before their 75th birthday in 2017, compared with just over 41,000 three years earlier.