Amazon’s websites are hawking a universe of dangerous, pseudoscience health products — from electronic "zappers" that promise to cure HIV to bleach enemas for autism.

That’s according to an investigation by UK’s Sun newspaper, which accuses the internet giant of profiting off people’s desperation and illness by selling unproven, snake-oil products.

In a quick search of Amazon.com, I found that many of the dubious products mentioned in the Sun’s story are also available to US consumers. For example, at the click of a button, consumers can order Dr. Reckeweg’s "Tumor Drops," which promise to be a "supplementary medication in the treatment of malignancy" after a cancer operation or radiation therapy.

Similarly, Amazon sells the MMS Handbook, which offers suggestions on how to concoct a dangerous bleach solution that treats everything from autism to HIV, hepatitis, and cancer. The Food and Drug Administration has warned of the dangers of MMS, also known as the "Miracle Mineral Solution":

The product instructs consumers to mix the 28 percent sodium chlorite solution with an acid such as citrus juice. This mixture produces chlorine dioxide, a potent bleach used for stripping textiles and industrial water treatment. High oral doses of this bleach, such as those recommended in the labeling, can cause nausea, vomiting, diarrhea, and symptoms of severe dehydration.

Plugging the words "cancer cure" into Amazon opened up a world of equally misleading products, including many immune system boosters. These are totally ineffective. People can’t boost their immune systems by taking unproven pills or drops. Still, many consumers have bought into the hype. In one review on Amazon’s page, here’s a mother writing about Birm, an immune system booster from Ecuador:

We purchased this product, as our daughter is battling cancer and thought it may help her immune system. Birm so far has worked great and our daughter who was getting ill on a regular basis has felt good and no issues. An acquaintance of our's has cancer as well and refused chemo. She started taking birm and changed her diet and when she returned for a DR. visit,the cancer markers had reduced from 88 to 50.

Amazon also has hundreds of metabolism boosting products for sale. Again, there’s nothing people can take or eat that’s been proven speed up their metabolism, as I’ve explained here.

There were numerous products claiming to be the hormone oxytocin, including a nasal spray that allegedly "Manages stress levels," "Reduces cravings for sweets," and "Increases sexual receptiveness & orgasms." If the product is fake, it’s misleading and potentially dangerous. (Who knows what's in it?) If it’s real, it may also be dangerous since oxytocin is a hormone that interacts with the brain in ways even researchers don't fully understand.

Most surreal are Amazon's offering of "snake oils," which claim to deliver health and beauty fixes, from strengthening hair, to acting as a "botox alternative." That includes one snake oil, which, the site warns, "does not contain oil from a snake."

Why can Amazon peddle such quackery?

There’s one, key reason why Amazon can sell these dubious health products. Many of them fall in the category of dietary supplements, which are very loosely regulated by the FDA. Unlike drug makers, supplement makers don't need to prove their products are safe or even effective before putting them on store shelves, digital or otherwise.

"A lot of supplements can make claims about health benefits as long as there is a disclaimer," said Gregg Gonsalves, a Yale research scholar who has studied the FDA. "So Amazon is just making a buck off of a system that doesn't rigorously regulate these products."

If product-makers boast health claims that are similar to the kinds you'd typically see on drugs — promising to cure a disease or impact an organ system in a particular way – then FDA would have jurisdiction to go after them. (And it seems some of the products on the Amazon site would fall into that category.)

The Federal Trade Commission also has the legal authority to prosecute people who mislead and injure consumers. They could even go after Amazon for selling these products, as they have in the past when the site sold bamboo products that contained no bamboo. But they can’t go after every little fish in the sea of quackery out there, so some of these products may simply fall through the gaps.

As Mary Engle, head of the FTC's Ad Practices Division, told Vox, "Unfortunately the internet is full of unsubstantiated claims. So we have to decide where we're going to spend our limited resources."

In theory, Amazon could take a stand against quackery and introduce some minimum quality or scientific requirements before selling useless supplements and "cures" to groups like cancer patients.

I emailed and called Amazon public-relations representatives to ask about the problematic products. Three days after my initial inquiries, I got an email from Amazon PR man Erik Fairleigh: "We won't be commenting." So until Amazon decides to take more responsibility for what it sells, consumers will have to sniff out the quackery themselves.