20dec multivitamin benefits hero
22 December 2020

Multivitamin “benefits” may just be placebo effect

No measurable health benefits from taking multivitamins, study finds.

Multivitamins are big business, with supplement companies earning millions of dollars a year from sales. But good evidence regular multivitamin use has any measurable effect on health is yet to be found.

A new study published in the journal BMJ Open found any benefits of taking multivitamins may be “all in the minds of users”.

The study analysed data on more than 21,000 US adults. Nearly 5000 regularly took supplements while 16,000 didn’t.

Participants were asked to rate their own health. They were also asked about their psychological, physical and functional health outcomes, and history of 10 long-term health problems.

Regular vitamin takers were 30 percent more likely to rate their overall health as “excellent or good”. However, there was no difference between participants in any clinical health outcomes, including high blood pressure, diabetes, asthma and arthritis.

The study backs up findings of other research that’s also found no clinical health benefits from vitamin use in the general population.

Regular multivitamin users in the study were significantly older and had higher household incomes. They were also more likely to be women, college graduates, married and have health insurance.

The majority of vitamin supplements “are sold to the so-called ‘worried well’ population who may assign greater weight to the purported health benefits of dietary supplements and alternative therapies,” the study’s authors note.

“It is possible that members of this population are more susceptible to positive expectations and may therefore continue to use [multivitamins] in the absence of clinical benefits.”

Our advice

  • Unless a supplement is recommended by your doctor, you’re better off spending your money on eating a balanced diet.

  • If you’re looking for something to boost your health and reduce your risk of disease, walk past the supplement store – and keep going. Regular physical activity reduces your risk of dying early, no matter the cause.

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Neil S.
27 Dec 2020
The Issue

For me the issue is not whether multivitamin tabs are useful for the wider population or whether the money would be better spent on maintaining a healthy diet which, for most New Zealanders, is reasonably attainable.
In fact, I venture to suggest that anyone who can afford to buy multivitamin tablets could easily afford the cost of maintaining a healthy diet.
My firm understanding is that, apart from selenium which is not a vitamin anyway, an adequate balanced diet meets the nutritinal needs of the vaste majority of NZers.

M Smith
27 Dec 2020
Insufficient scientific information for this article to be useful

The article is unbalanced in that it looks at only one study and makes all supplements sound useless, whereas I doubt this is true. There is insufficient information in this article to know exactly what kinds of supplements were examined during the study. If the study didn't capture this information then it is not very scientific. Exactly what was in the supplements examined? Was it just supplements containing multiple vitamins that are present in concentrations too low to be useful? Did the supplements contain minerals? Did the study include single ingredient supplements? Iron and Vit B12 supplements, for example, would be beneficial for a vegan. I have found magnesium is the only thing that prevents nightly agonising leg cramps. While I agree that many multivitamins are a waste of money, this article appears to write off everything, saying to bypass the supplement store altogether. It would be more useful for consumers if you could run a longer article that examines multiple studies and look at specific ingredients. Try looking in the Cochrane database as a start.

Bruce S.
27 Dec 2020
Facts Versus Opinions

I worry when I see people that claim their opinion is right and if you disagree you are the enemy? So let's attack you personally. Whatever happened to a healthy debate on the facts?

Scientific facts that benefit us in everyday life comes from diligent testing/evaluation over a large number of studies. The averaged results of many studies have always been proven to be more reliable than single studies.

Dr Rucklidge's studies of supplements helping growing children with mental issues or farmers with growing livestock are not the same as supplements for grown adults. Supplements for people that are ill with a specific condition versus mostly healthy people are also not comparable in study terms.

Also, size matters - a study like Dr Rucklidge with 79 people or a study with 21,000. The smaller will always have a higher risk of being wrong. Other factors can also affect the outcome so no one study should be considered,

20 years of large credible studies, most from government bodies (not single researchers) with large numbers of participants have so far averaged out to prove multi-vitamins are a waste of money for adults.

If you want to consider the facts and not opinions always look for studies that average all the other studies. Here is one example on multivitamins from nutrition facts .org https://www.youtube.com/watch?v=5fgVDT0qw88&feature=youtu.be

I will however defend your right to waste your money if it makes you feel good. No need to justify. I waste my money on feel good stuff as well - just not multivitamins.

Nigel W.
26 Dec 2020
Doesn't add up.

If vitamin and mineral supplements have no measurable benefit why do farmers spend so much on stock feed and supplements for their livestock which essentially provides the same supplements for animals? Farmers do not spend money unless it results in measurable returns to the bottom line.

Also, there is evidence to support that a lot of the food available in supermarkets today, (including fresh foods) do not have all the nutrients we need due to intensive farming techniques. Modern lifestyles mean people are less likely to eat healthy balanced diets as well.

For these reasons alone, vitamin and mineral supplements make good sense as part of any balanced diet.

26 Dec 2020
...it doesn't!

Absolutely agree. I get tired of 'scientific' studies. People aren't stupid - if a supplement isn't doing what it says it will they won't keep paying for it. I know exactly what works for me - through experimentation and the results, or lack of. Science puts everything in a box.

Jordan K.
26 Dec 2020
Superficial, Unbalanced, Banal & Juvenile Reporting

This is irresponsible "research" and "reporting" on behalf of Consumer personnel / management, and is concerning if it is a reflection of the interests the organisation is seeking to appease behind the scenes.

For a start, why single out one, solitary study on which to make such blanket, and hard and fast, conclusions and recommendations? Secondly, how about reporting on the financial / funding backing of the "study / research" it is holding up as a single source of truth?

Not impressed.

And no, I have no alliance with, or allegiance to, anyone or any entity in the vitamin manufacturing or sales field. In fact, I think that sector is indeed rife with ridiculous profit margins, all the way through. BUT that doesn't equate to having or touting a blanket and biased opinion on their products.

And the hallowed position this Consumer writer and associated editorial personnel attributes to the average GP is both outdated and naiive. And, it seems highly likely, designed to keep in tow with Big Pharma, the medical industry, and related government agencies.

Gutless, irresponsible, shallow writing for readers of a far lesser intellectual calibre than I though Consumer would actually have.

Gary B.
22 Dec 2020
Not consistent with Canterbury University research

Google the studies published by Dr Julia Rucklidge at University of Canterbury. Her work on mental health and nutrition is groundbreaking and well worth looking into. I wouldn't be too quick to dismiss the value of multivitamins based on a BMJ study. Also to add, the training given to Drs whilst studying medicine is a minimal number of hours. Whether or not you receive good advice from your GP on diet very much depends on their individual learning and experience in the nutrition field.

Douglas & Linda K.
27 Dec 2020
Good diet is important

Thanks for the link to Julia Rucklidge at Canterbury University. I treat vitamins as a supplement to a good diet - I always have them with food - vitamins, minerals and phyto-nutrients - the vitamins are from plants, not synthetic. SInce taking them I have not needed antibiotics for annual sinus problems - sinus problems gone. Admittedly not a scientific trial, but I am thrilled not to take anti-biotics.