Connect with us

Supplements

Do Vitamin C Supplements Cause Kidney Stones? – Care2.com

Published

on


Mainstream medicine has long had a healthy skepticism of dietary supplements, extending to the present day with commentaries like “Enough is enough.” In an essay entitled “Battling quackery,” however, published in the Archives of Internal Medicine, it’s argued that we may have gone too far in our supplement bashing, as evidenced by our “uncritical acceptance” of supposed toxicities; the surprisingly “angry, scornful tone” found in medical texts using words like “careless,” “useless,” “indefensible,” “wasteful,” and “insidious”; and ignoring evidence of possible benefit.

“To illustrate the uncritical acceptance of bad news” about supplements, the authors discussed the “well-known” concept that high-dose vitamin C can cause kidney stones, as I highlight in my video Do Vitamin C Supplements Prevent Colds but Cause Kidney Stones?. Just because something is well-known in medicine, however, doesn’t mean it’s necessarily true. In fact, the authors couldn’t find a single, reported case.

We’ve known that vitamin C is turned into oxalates in the body, and, if the level of oxalates in the urine gets too high, stones can form, but, even at 4,000 mg of vitamin C a day, which is like a couple gallons’ worth of orange juice, urinary oxalates may not get very high, as you can see at 1:10 in my video. Of course, there may be the rare individuals who have an increased capacity for this conversion into oxalates, so a theoretical risk of kidney stones with high-dose vitamin C supplements was raised in a letter printed in a medical journal back in 1973.

When the theoretical risk was discussed in the medical literature, however, the researchers made it sound as if it were an established phenomenon: “Excessive intake of vitamin C may also be associated with the formation of oxalate stones.” Sounds less like a theoretical risk and more like an established phenomenon, right? That statement had seven citations supposedly suggesting an association between excessive vitamin-C intake and the formation of oxalate kidney stones. Let’s look at the cited sources, which you can see from 1:47 in my video. One reference is the letter about the theoretical risk, which is legitimate, but another listed citation, titled “Jaundice following the administration of niacin,” has nothing to do with either vitamin C or kidney stones. What’s more, the other five citations are just references to books. That may be acceptable if the books cited primary research themselves, but, instead, there was a kind of circular logic, where the books just cite other books citing that theoretical risk letter again. So, while it looks as if there’s a lot of evidence, they’re all just expressing this opinion with no new data.

By that time, there actually were studies that followed populations of people taking vitamin C supplements and found no increased kidney stone risk among men, then later, the same was shown in women. So, you can understand the frustration of the authors of “Battling quackery” commentary that vitamin-C supplements appeared to be unfairly villainized.

The irony is that we now know that vitamin-C supplements do indeed appear to increase kidney stone risk. The same population of men referenced above was followed further out, and men taking vitamin-C supplements did in fact end up with higher risk. This has since been confirmed in a second study, though also of men. We don’t yet know if women are similarly at risk, though there has now also been a case reported of a child running into problems.

What does doubling of risk mean exactly in this context? Those taking a thousand milligrams or so of vitamin C a day may have a 1-in-300 chance of getting a kidney stone every year, instead of a 1-in-600 chance. One in 300 “is not an insignificant risk,” as kidney stones can be really painful, so researchers concluded that since there are no benefits and some risk, it’s better to stay away.

But there are benefits. Taking vitamin C just when you get a cold doesn’t seem to help, and although regular supplement users don’t seem to get fewer colds, when they do get sick, they don’t get as sick and get better about 10 percent faster. And, those under extreme physical stress may cut their cold risk in half. So, it’s really up to each individual to balance the potential common cold benefit with the potential kidney stone risk.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations—2015: Food as Medicine: Preventing and Treating the Most Dreaded Diseases with Diet, and my latest, 2016: How Not to Die: The Role of Diet in Preventing, Arresting, and Reversing Our Top 15 Killers.

Related on Care2:

[embedded content]

Let’s block ads! (Why?)



Source link

Supplements

"You're Just Peeing Out a Lot of Money." This Is the Real Way You're Flushing Your Retirement Savings Down the Drain – MONEY

Published

on

By


| Money

this link is to an external site that may or may not meet accessibility guidelines.

Let’s block ads! (Why?)



Source link

Continue Reading

Supplements

FDA Sends Warning Letters on Dietary Supplements – Wall Street Journal

Published

on

By


The FDA has sent warning letters to companies marketing dietary supplements.


Photo:

Jacquelyn Martin/Associated Press

The U.S. Food and Drug Administration said it sent warning letters to 11 companies for marketing dietary supplements that don’t meet its guidelines.

The agency issued warnings to three companies for marketing dietary supplements containing phenibut, which is sometimes sold as a sleep aid or to treat anxiety. It said that phenibut doesn’t meet the statutory definition of a dietary ingredient, which is generally a vitamin, herb or other natural substance used to supplement the diet. 

A Wall Street Journal article last week on the $40 billion supplement industry said that phenibut, developed as a drug in the former Soviet Union, was being marketed as a “nootropic,” or brain supplement, in the U.S. A spokeswoman for the FDA said that the agency was already investigating phenibut.

The FDA also issued warnings to eight companies for marketing dietary supplements containing DMHA, a stimulant sometimes found in exercise and weight-loss supplements. The companies have 15 business days to inform the FDA of steps they will take to bring their products into compliance. That could include a decision to recall, reformulate or discontinue sales.

Supplements aren’t tightly regulated by the FDA like prescription drugs. Dietary-supplement manufacturers don’t need approval from the FDA before introducing their products to the market. The FDA has oversight for taking action against any misbranded supplement after it reaches the market.

The FDA said it is launching a new online tool to help warn consumers of ingredients that appear to be unlawfully marketed in supplements. The agency said the Dietary Supplement Ingredient Advisory List will help get cautionary information to the public more quickly before it issues any final determination. It is on the FDA website, and consumers can also sign up to receive updates and changes to the list.

Write to Anne Marie Chaker at anne-marie.chaker@wsj.com

Let’s block ads! (Why?)



Source link

Continue Reading

Supplements

New Tool Alerts Public to Unlawfully Marketed Dietary Supplement Ingredients – The Cardiology Advisor

Published

on

By


In an effort to better alert the public of unlawful ingredients in dietary supplements, the Food and Drug Administration (FDA) has created the Dietary Supplement Ingredient Advisory List, a new reference tool for consumers and manufacturers.

Available on the FDA website, the list includes ingredients that may not lawfully be included in dietary supplements. Consumers may wish to avoid supplements that include these ingredients as they may not fit the definition of a dietary ingredient or may require pre-market notification that was not submitted; inclusion in this list does not necessarily mean the ingredient poses a safety concern.

“It is important to note that the List is not exhaustive; it will always be a work in progress,” said Frank Yiannas, the FDA’s Deputy Commissioner for Food Policy and Response. “We expect the List will evolve as new ingredients are identified and others are removed.” In addition, the FDA will continue to communicate with the public regarding any safety concerns identified with new dietary supplement ingredients.

In a press statement, Yiannas also noted that the agency recently sent out warning letters to 8 companies that were marketing dietary supplements containing DMHA and 3 companies marketing supplements with phenibut; neither one of these currently meets the FDA’s definition of a lawful dietary ingredient. “We take these violations very seriously and stand ready to take enforcement action without further notice if the companies do not immediately cease distribution of the products,” said Yiannas. In February 2019, the FDA went after 17 companies selling unapproved and/or misbranded products (most sold as dietary supplements) claiming to prevent, treat, or cure Alzheimer disease and other serious disease and health conditions.

Consumers who wish to receive alerts related to updates to the Dietary Supplement Ingredient Advisory List can sign up here.

For more information visit FDA.gov.

Related Articles

This article originally appeared on MPR

Let’s block ads! (Why?)



Source link

Continue Reading

Trending