Well over 50% of Australians take some form of supplementation on a daily basis. Two of the most commonly used supplements are multivitamins or some type of omega 3 fatty acid, typically fish or krill oil.
But, two recent, very extensive reviews published in well-respected medical journals have suggested no harm or benefit from regularly taking multivitamins. The first published in one of the Circulation journals, “Cardiovascular Quality and Outcomes” pooled data from 18 randomised controlled trials and cohort studies including around 2 million people, showing no major benefits from the regular ingestion of multivitamins. These people were followed for an average of 12 years but the longer studies were not randomised controlled trials.
The second review published by Dr Lee Hooper and her group was a large Cochrane review of 79 randomised controlled trials involving 112,059 patients, again showing no benefits from the regular use of some form of omega 3 fatty acids, especially supplementation but also included foods that have a high level of omega 3.
Both reviews focused on cardiovascular outcomes such as heart attack, stroke and cardiac associated death.
So, is this the end of the story? Are supplements purely a waste of money with no evidence to support such widespread use? Both these reviews included an enormous amount of people and were based firstly on the gold standard of medical science, the randomised controlled trial where one group was given the active therapy and the other half, placebo controlled. There was, however, a large contribution from cohort studies. This is where one group takes the active component compared with people who have chosen to not take the active component, but who have similar demographics.
Many human beings are seeking a magic pill that will allow them to continue their many poor lifestyle choices, but still offer some protection against many of our common killers, in particular cardiovascular disease and cancer.
That’s the first problem.
No one can take any form of pill or potion, either pharmaceutical or complementary, and expect it will protect them from the consequences of poor lifestyle choices.
Before you put any pill in your mouth, you derive the greatest benefit from lifestyle modification. A recent trial from Holland, the MORGEN trial demonstrated those people who follow the five keys to ultimate health i.e. no addictions, good sleep, healthy nutrition, 3 to 5 hours of exercise per week and achieving happiness, peace & contentment have an 83% reduction in cardiovascular disease compared with those who are in the poorest categories for lifestyle behaviours.
Now, here’s the key to the entire argument. Drugs are like a high-performance motor vehicle, taking you from A to B very quickly but with the potential of crashing and killing or harming yourself along the way, thus the need for strict road rules, high level safety equipment in the car and seat belts. Supplements, however, are like bicycles which take you from A to B much slower, but with less risk of harm and also the added benefits of exercise. Randomised controlled trials are relevant and important for any trials involving drugs because of the strong effects and possible strong side effects of pharmaceutical preparations. Vioxx (as one example) was seen as the new miracle drug for arthritis but after it had been on the market for 10 years it was shown to double risk of heart attack and thus was withdrawn.
No evidence of any death or major harm from the long-term use of supplements has ever been reported, but that’s the key — long-term. The best epidemiology study in the world, in my opinion, has been the combined Nurses Health Study and Male Physicians Trial performed by Harvard University. One component of these trials showed no benefit from multivitamins taken up to 10 years. But in the Male Physicians Trial at 10 years, there was an 8% reduction in common cancers and cataracts. When the observational data from the Nurses Health Study was analysed at 15 years, there was a 75% reduction in bowel cancer, a 25% reduction in breast cancer and a 23% reduction in cardiovascular disease in the nurses who took a multivitamin daily for 15 years compared with those who didn’t.
The 20 year data from the Male Physicians Trial was recently released demonstrating a 44% reduction in cardiovascular disease. Firstly, it is a huge commitment to your health, to take a multivitamin daily for 20 years, considering that for the general population, 50% have stopped taking any form of therapy whether it be pharmaceutical or complementary, 12 months after it was prescribed or recommended.
The second review showed no cardiovascular benefit from omega 3 therapy such as fish or krill oil in the reviewed 79 randomised controlled clinical trials of just over 112,000 people but again, it’s the same principle. The studies ran for somewhere between 1 to 6 years, the vast majority being less than five years showing no cardiovascular benefits. A recent review published in Mayo Clinic Proceedings (Jan 2017) again showed that trials of Omega 3 lasting for less than 5 years showed no benefit but the trials longer than five years showed an 18% reduction in cardiovascular disease.
There are clear messages from both of these reviews
1) There is no cardiovascular benefit from taking multivitamins or Omega 3 oils in the short-term i.e. less than five years.
2) Most of the studies were done in high risk patients i.e. those with established cardiovascular disease or multiple risk factors for heart disease.
3) It is unlikely there will ever be any major, long-term randomised controlled clinical trial of supplementation in any population (i.e. longer than 10 years), because of the lack of short-term data (therefore the belief by researchers that these therapies don’t work, so why bother), the enormous expense of the trial for the group performing the study and the lack of patents on the supplements, thus if benefits were shown it would be open slather for any company to sell the supplements without contributing to the initial research.
So, in reality, there is a large body of evidence showing an enormous benefit on cardiovascular risk markers from the regular ingestion of multivitamins and omega 3 fatty acids but the studies to date show the benefits only start to manifest after long term (at least five years or longer) and only in people who follow healthy lifestyle principles.
I have had a number of patients in my practice who have told me, “I took vitamins for a few months and didn’t feel any different, so I stopped!”
With our current level of evidence, I will continue to take supplements long-term but just like addressing healthy lifestyle principles, it must be a long-term commitment to achieve any benefit. I believe that all these two major reviews of multivitamins and Omega 3s prove is that taking supplements for a short period of time in high-risk people is too little, too late. Surely the best treatment of any condition is prevention and the earlier you start preventative health strategies, the better chance you have of preventing major illnesses.