Multivitamins and chocolate do not improve brain or cardiovascular health. A personal perspective. Naresh Chand, Ph.D., Courtesy of ADRxSynergy

?

?

Multivitamins and chocolate do not improve brain or cardiovascular health. A personal perspective. Naresh Chand, Ph.D., Courtesy of ADRxSynergy

?

?

Multivitamins and Dementia: Untangling the COSMOS Study

Christopher Labos, MD CM, MSc. Multivitamins and chocolate do not improve brain or cardiovascular health (2,3). What is not good for the heart is not good for the brain.

?

Dr. Chand thanks Christopher Labos, MD CM, MSc, for his vision and perspective (2). Most people are na?ve about statistics or the art of fooling most people. We spend >$50 billion on dietary supplements in the USA each year. Sadly, many of these products end up in junkyards after a few months or years.

?

A personal perspective: After a life-threatening stroke (Nov 18, 1998), Dr. Chand did not take any chocolate, vitamins, or other dietary supplements, except consuming Plant-based foods (1) to optimize the health and nutrition of >100 trillion gut microbiota- Thanks to Dr. Neal Barnard. ?

?

Dr. Chand is surprised to be living healthier and longer. He believes cooking foods and herbs/spices often activates naturally packed phytonutrients and fibers in greens, beans, whole grains, or ancient grains and offers synergistic health benefits at molecular or subcellular multiple levels (1).

?

More than 80% of people in the world rarely take vitamins, minerals, and or extracts of foods and herbs. However, they use ancient cooking practices (1).

?

1. https://www.youtube.com/watch?v=WqwLRJ123iY ? They spend 1/100 to 1/1000 on healthcare.

???https://www.dhirubhai.net/in/dr-naresh-chand-46051a73/recent-activity/all/

?

2.https://www.medscape.com/viewarticle/996926?ecd=wnl_infocu1_broad_broad_persoexpansion-algo_20231018_etid5965875&uac=317473DY&impID=5965875#vp_2

3. https://www.sciencedirect.com/science/article/pii/S0002916523047172?via%3Dihub ?Homocysteine lowering by using B vitamins had no significant effect on individual cognitive domains or global cognitive function or on cognitive aging.

?

?

?

?

?

?

?


Christopher Labos, MD CM, MSc

I have?written before ?about the?COSMOS study ?and its finding that multivitamins (and chocolate) did not improve brain or cardiovascular health. So I was surprised to read that a "new" study found that vitamins can forestall dementia and age-related cognitive decline. Upon closer look, the new data are neither new nor convincing, at least to me.

Chocolate and Multivitamins for CVD and Cancer Prevention

The large randomized?COSMOS trial , was supposed to be?the?definitive study on chocolate that would establish its heart-health benefits without a doubt. Or, rather, the benefits of a cocoa bean extract in pill form given to healthy, older volunteers. The COSMOS study was negative. Chocolate, or the cocoa bean extract they used, did not reduce cardiovascular events.

?

And yet for all the pre-publication importance attached to COSMOS, it is scarcely mentioned. Had it been positive, rest assured that Mars, the candy bar company that co-funded the research, and other interested parties would have been shouting it from the rooftops. As it is, they're already?spinning it .

Which brings us to the multivitamin component. COSMOS actually had a 2 × 2 design. In other words, there were four groups in this study: chocolate plus multivitamin, chocolate plus placebo, placebo plus multivitamin, and placebo plus placebo. This type of study design allows you to study two different interventions simultaneously, provided that they are independent and do not interact with each other. In addition to the primary cardiovascular endpoint, they also studied a cancer endpoint.

?

The multivitamin supplement?didn't reduce cardiovascular events ?either. Nor did it affect cancer outcomes. The main COSMOS study was negative and reinforced what countless other studies have proven: Taking a daily multivitamin does not reduce your risk of having a heart attack or developing cancer.

But Wait, Theres More: COSMOS-Mind

But no researcher worth his salt studies just one or two endpoints in a study. The participants also underwent neurologic and memory testing. These results were reported separately in the?COSMOS-Mind study .

COSMOS-Mind is often described as a separate (or "new") study. In reality, it included the same participants from the original COSMOS trial and measured yet another primary outcome of cognitive performance on a series of tests administered by telephone. Although there is nothing inherently wrong with studying multiple outcomes in your patient population (after all, that salami isn't going to slice itself), they cannot all be primary outcomes. Some, by necessity, must be secondary hypothesis–generating outcomes. If you test enough endpoints, multiple hypothesis testing dictates that eventually, you will get a positive result simply by chance.

?

There was a time when the neurocognitive outcomes of COSMOS would have been reported in the same paper as the cardiovascular outcomes, but that time seems to have passed us by. Researchers live or die by the number of their publications, and there is an inherent advantage to squeezing as many publications as possible from the same dataset. Though, to be fair, the journal would probably have asked them to split up the paper as well.

?

In brief, the cocoa extract again fell short in COSMOS-Mind, but the multivitamin arm did better on the composite cognitive outcome. It was a relatively small difference — a 0.07-point improvement on the z-score at the 3-year mark (the z-score is the mean divided by the standard deviation). Much was also made of the fact that the improvement seemed to vary by prior history of cardiovascular disease (CVD). Those with a history of CVD had a 0.11-point improvement, whereas those without had a 0.06-point improvement. The authors couldn't offer a definitive explanation for these findings. Any argument that multivitamins improve cardiovascular health and therefore prevent?vascular dementia ?has to contend with the fact that the main COSMOS study didn't show a cardiovascular benefit for vitamins. Speculation that you are treating nutritional deficiencies is exactly that: speculation.

?

A more salient question is: What does a 0.07-point improvement on the z-score mean clinically? This study didn't assess whether a multivitamin supplement prevented dementia or allowed people to live independently for longer. In fairness, that would have been exceptionally difficult to do and would have required a much longer study.

Their one attempt to quantify the cognitive benefit clinically was a calculation about normal age-related decline. Test scores were 0.045 point lower for every 1-year increase in age among participants (their mean age was 73 years). So the authors contend that a 0.07-point increase, or the 0-083 point increase that they found at year 3, corresponds to 1.8 years of age-related decline forestalled. Whether this is an appropriate assumption, I leave for the reader to decide.

COSMOS-Web and Replication

The results of COSMOS-Mind were seemingly bolstered by the recent publication of?COSMOS-Web . Although I've seen this study described as having replicated the results of COSMOS-Mind, that description is a bit misleading. This was yet another ancillary COSMOS study; more than half of the 2262 participants in COSMOS-Mind were also included in COSMOS-Web. Replicating results in the same people isn't true replication.

The main difference between COSMOS-Mind and COSMOS-Web is that the former used a telephone interview to administer the cognitive tests and the latter used the internet. They also had different endpoints, with COSMOS-Web looking at immediate recall rather than a global test composite.

COSMOS-Web was a positive study in that patients getting the multivitamin supplement did better on the test for immediate memory recall (remembering a list of 20 words), though they didn't improve on tests of memory retention, executive function, or novel object recognition (basically a test where subjects have to identify matching geometric patterns and then recall them later). They were able to remember an additional 0.71 word on average compared with 0.44 word in the placebo group. (For the record, it found no benefit for the cocoa extract).

Everybody does better on memory tests the second time around because practice makes perfect, hence the improvement in the placebo group. This benefit at 1 year did not survive to the end of follow-up at 3 years, in contrast to COSMOS-Mind, where the benefit was not apparent at 1 year and only seen at year 3. A history of cardiovascular disease didn't seem to affect the results in COSMOS-Web as it did in COSMOS-Mind. As far as replications go, COSMOS-Web has some very non-negligible differences compared with COSMOS-Mind. This incongruity, especially given the overlap in the patient populations is hard to reconcile. If COSMOS-Web was supposed to assuage any doubts that persisted after COSMOS-Mind, it hasn't for me.

One of These Studies Is Not Like the Others

Finally, although the COSMOS trial and all its ancillary study analyses suggest a neurocognitive benefit to multivitamin supplementation, it's not the first study to test the matter. The?Age-Related Eye Disease Study ?looked at vitamin C,?vitamin E , beta-carotene,?zinc , and copper. There was no benefit on any of the six cognitive tests administered to patients.?The Women's Health Study , the?Women's Antioxidant Cardiovascular Study , and?PREADViSE ?have all failed to show any benefit to the various vitamins and minerals they studied. A?meta-analysis of 11 trials ?found no benefit to B vitamins in slowing cognitive aging.

?

要查看或添加评论,请登录

Dr. Naresh Chand的更多文章

社区洞察

其他会员也浏览了