A new investigation has found that many popular protein powders and shakes may contain potentially dangerous levels of toxic heavy metals, including lead — though not all experts agree on how much risk they actually pose.

Consumer Reports tested 23 popular protein products and found more than two-thirds contained more lead per serving than the outlet's experts consider is safe in a single day. Some had more than 10 times what some health experts consider a safe daily amount, according to the report published this week.

"We advise against daily use for most protein powders, since many have high levels of heavy metals and none are necessary to hit your protein goals," said Tunde Akinleye, a chemist and food safety researcher at Consumer Reports.

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Plant-based products — especially those made with pea protein — were the worst offenders, averaging about nine times more lead than dairy- and beef-based counterparts. The investigation included both ready-to-drink shakes and powders intended for blending into smoothies.

Some single servings contained between 400% and 1,600% of Consumers Reports' recommended daily limit for lead, or 4 to 16 times higher than what it considers safe. For those that were slightly lower, experts recommended limiting consumption to once a week.

Several also contained measurable cadmium and arsenic, with cadmium levels in some cases more than twice what public health authorities consider potentially harmful daily exposure.

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Dairy-based protein powders and shakes generally had the lowest amounts of lead, the investigation found, though many still had enough for Consumer Reports' experts to caution against daily use. Lead levels in the beef-based products were about half those of plant-based products on average. Most fell below Consumer Reports' daily level of concern, though some exceeded it, and experts say these were safe to consume "occasionally."

Most of those that they said were better choices for daily consumption were dairy, made using whey, which is a byproduct of the cheese-making process.

No amount of lead is technically safe, the report noted, but the greatest danger comes from repeated or continuous exposure, particularly at high doses, and is especially risky for children, pregnant women and older adults.

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"There’s no reason to panic if you’ve been using any of the products we tested, or if you take protein supplements generally," the report noted. "Many of these powders are fine to have occasionally, and even those with the highest lead levels are far below the concentration needed to cause immediate harm." 

It continued, "That said, because most people don’t actually need protein supplements — nutrition experts say the average American already gets plenty — it makes sense to ask whether these products are worth the added exposure."

The Recommended Dietary Allowance (RDA) for protein is 46 grams per day for women and 56 grams for men. Very active individuals may need nearly twice that amount, but experts say most people can easily meet their needs through food alone — despite the recent craze driving a multibillion-dollar wellness trend marketed as a shortcut to build muscle.

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"The average adult doesn't require protein supplements to hit their daily quota," said Lisa Moskovitz, a registered dietitian and founder of NY Nutrition Group in Manhattan. "Yet, at a time when protein intake is trending and all we seem to hear is about the importance of consuming enough, many of my clients are incorporating more protein powders than ever before."

If you're looking for a protein supplement, Moskovitz recommends whey-based options, not only because of the lower lead levels but also because whey is better absorbed and utilized by the body.

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Still, she and other experts say the alarm may be overblown.

Dr. Andrea Love, a Pennsylvania-based biomedical scientist, slammed the investigation as "fearmongering," noting the lead levels identified were measured in parts per billion and remained far below the daily exposure limits considered safe for adults.

Moskovitz said the evaluation was based on "extremely conservative and controversial parameters." Still, she advised choosing brands that are third-party tested and show lower levels of lead.

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Long-term lead exposure can harm the brain and heart, she noted, while short-term symptoms may include nausea, vomiting, headache and fatigue.

Heavy metals occur naturally in the environment, she added, and even everyday foods such as spices, dried fruit, rice and certain vegetables can contain trace amounts absorbed from soil and water.

"The FDA doesn’t regulate supplements before they hit the market," Moskovitz told Fox News Digital. "That is why it's always advised to be vigilant, aware and consult with a professional if you're unsure whether a product is safe or unsafe."

NEW YORK, N.Y. - At least 100,000 people descended upon New York City’s Times Square on Saturday for the "No Kings" protest and Fox News Digital spoke to more than half a dozen of them about why they took to the streets to rally against President Trump.

"Because I'm an American and I learned from history, unlike a lot of other people in this country. History repeats itself," a man named Ed told Fox News Digital when asked why he came to the rally.

"People don't seem to understand that, and we're going down a slippery slope, probably halfway down there already, and if we don't stand up and protest and expand our message across America, we'll be just another one of what Trump called the s***hole countries. That's where he's leading us." 

The rally was peaceful as protesters gathered in Times Square and marched down 7th Avenue holding a variety of signs, some more inflammatory than others.

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"No fuhrers," one sign said along with a crossed-out swastika. Another sign read, "ICE melts faster under pressure," a reference to United States Immigration and Customs Enforcement, an agency where agents have faced a 10-fold increase in violence against them over the past few months.

"We have a fascist government in America abetted by a fascist media," a man named Brad told Fox News Digital. "And people need to have their voices be heard. There's this idea that somehow that Trump stands for America. He stands for nothing like that, he stands for hate, he stands for everything against the Constitution, everything our values are built upon, and he stands for himself and his friends and not for the great American people."

A woman named Nicole told Fox News Digital part of her motivation for attending is that she is recovering from cancer and her husband was recently diagnosed with cancer and says she received a notice their health insurance would be canceled in July 2026.

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"So we can bomb random boats off the coast of Venezuela, spend all this money on ICE terrorizing people, so we can take food and health care away from families," Nicole said. "It's disgusting."

Laura, who said she is from Seattle but was on vacation in New York City and decided it was important to come to the rally, told Fox News Digital of her belief that if people don’t "collectively" get the message of disapproval out "then we’re going to just give up."

"We just might as well bend over," Laura said, adding that she is married to a woman and is concerned that under Trump, that marriage "might not be valid anymore."

"That’s f****** bull****," Laura said. 

Fox News Digital watched as a man dressed in yellow placed an Antifa sticker onto a street sign as protesters walked by. Several users on social media posted signs mentioning Antifa, which Trump designated as a domestic terrorist organization earlier this year. 

Many of the signs at the protest used the term "fascist" to describe Trump and several labeled Trump and members of his administration as "Nazis."

When asked if it's fair to call Trump a "fascist", Laura said, "I mean, he's doing s*** that is outside of what our Constitution has said."

"He circumvented so many of our government's checks and balances. That, I mean, it's just, it is ridiculous. Not to mention making everyone who's in his cabinet, they have no experience, no intelligence, no like, consistency. They’re just a joke, so yeah."

A man named Edgar told Fox News Digital that "democracy is at stake" while another man, Lenny, referred to Trump as a "fool" and a "clown."

Large crowds gathered in major cities all across the United States on Saturday with anti-Trump protesters attempting to make the case that Trump is a king who has overstepped his authority.

The "No Kings" movement first gained national attention in June, when similar demonstrations were held in response to the Army’s 250th anniversary military parade.

Trump, along with Republicans in Congress in recent days, have pushed back on the "king" label.

"They say they’re referring to me as a king. I’m not a king," Trump told Fox News on Friday.

Asked about the protests and whether National Guard units would deploy to manage crowds, White House spokesperson Abigail Jackson told Fox News Digital, "Who cares?"