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Vitamins and supplements: what you need to know before taking them

Posted 03 February 2023

The Conversation

If you were to open your medicine cabinet right now, there’s a fair chance that you’d find at least one bottle of vitamins alongside the painkillers, plasters and cough syrup.

After all, people are definitely buying vitamins: in 2020, the global market for complementary and alternative medicines, which includes multivitamin supplements, had an estimated value of US$82.27 billion. The use of natural health products such as minerals and amino acids has increased – and continues to rise, partly driven by consumers’ buying habits during the COVID-19 pandemic.

People sought out vitamins C and D, as well as zinc supplements, as potential preventive measures against the virus – even though the evidence for their efficacy was, and remains, inconclusive.

Multivitamins and mineral supplements are easily accessible to consumers. They are often marketed for their health claims and benefits – sometimes unsubstantiated. But their … Read the rest

Older Americans Are ‘Hooked’ on Vitamins

Posted 18 April 2018

By Liz Szabo, Kaiser Health News April 3, 2018

When she was a young physician, Dr. Martha Gulati noticed that many of her mentors were prescribing vitamin E and folic acid to patients. Preliminary studies in the early 1990s had linked both supplements to a lower risk of heart disease.

She urged her father to pop the pills as well: “Dad, you should be on these vitamins, because every cardiologist is taking them or putting their patients on [them],” recalled Dr. Gulati, now chief of cardiology for the University of Arizona College of Medicine-Phoenix.

But just a few years later, she found herself reversing course, after rigorous clinical trials found neither vitamin E nor folic acid supplements did anything to protect the heart. Even worse, studies linked high-dose vitamin E to a higher risk of heart failure, prostate cancer and death from any cause.

Dr. Gulati Read the rest

Vitamin and Mineral Supplements What Doctors Need to Know

Posted 8 February 2018

From JAMA

Dietary supplementation is approximately a $30 billion industry in the United States, with more than 90 000 products on the market. In recent national surveys, 52% of US adults reported use of at least 1 supplement product, and 10% reported use of at least 4 such products.1 Vitamins and minerals are among the most popular supplements and are taken by 48% and 39% of adults, respectively, typically to maintain health and prevent disease.

Despite this enthusiasm, most randomized clinical trials of vitamin and mineral supplements have not demonstrated clear benefits for primary or secondary prevention of chronic diseases not related to nutritional deficiency. Indeed, some trials suggest that micronutrient supplementation in amounts that exceed the recommended dietary allowance (RDA)—eg, high doses of beta carotene, folic acid, vitamin E, or selenium—may have harmful effects, including increased mortality, cancer, and hemorrhagic stroke.2

In this Read the rest

Defects found in 32% of multivitamins

Posted 29 November 2017

ConsumerLab.com, a USA company, regularly evaluates products being sold in the USA. Their mission: “to identify the best quality health and nutritional products through independent testing”.

In a report released today, they make these points:

If you’re not careful, you might not get what you’ve bargained for. We discovered problems in 46% of the multivitamins we selected for testing. More specifically, the test showed that…

  • 12 multivitamins contained much less (as low as 24%) or much more (as high as 157%) vitamin A, vitamin D, folate from folic acid, and/or calcium than listed on labels.
  • Many supplements exceeded upper tolerable intake levels — possibly doing more harm than good.
  • Gummy vitamins were especially problematic: 80% failed testing
  • Four multivitamins in tablet form failed to break apart within the required time. One needed 3 hours to fully disintegrate, 5 times the
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