If you missed your chance to buy the so-called "Trump vitamins" six or seven years ago, don't fret.

It appears the vitamins that were once part of Republican presidential candidate Donald Trump's financial empire are still for sale on the website of the company that bought up the assets of The Trump Network after it failed.

For certain, the urine test that was promoted as a way to develop a personalized vitamin regimen is still around.

The PrivaTest is proudly displayed on that company's site as a "scientific window into your personal biochemistry."

Nutrition experts interviewed by Healthline say the problem is that there is no proof the Trump vitamins provided any benefit to the people who bought them.

And, the nutrition experts add, there is no such thing as a urine test that can determine if you have any vitamin deficiencies.

"It'd be nice if there was," said Katie Ferraro, a registered dietitian and assistant clinical professor of nutrition at the University of California, San Francisco, School of Nursing.

"Basically, this is all imaginary," added Pieter Cohen, assistant professor of medicine at the Cambridge Health Alliance in Massachusetts.

"I think it is fair to characterize the PrivaTest and Trump vitamins as part of a pseudoscientific health scheme," concluded Britt Hermes, a former naturopathic doctor and author of The Naturopathic Diaries blog.

The Supplement Industry

Concerns over the effectiveness of dietary supplements aren't a new phenomenon.

Consumers in the United States spent an estimated $21 billion on vitamins and herbal supplements in 2015. About half of Americans take multivitamins while a fifth take herbal supplements.

Despite the demand, the dietary supplement industry is pretty much unregulated.

Under The Dietary Supplemental Health and Education Act of 1994, vitamins don't need to be approved by the Federal Drug Administration (FDA).

The FDA does urge the industry to refrain from false statements and misleading labels, but there is little enforcement. For example, the FDA spot tests only about 1 percent of the 65,000 dietary supplements on the market.

Therefore, there weren't any laws broken by The Trump Network when it sold its urine test and vitamin regimen.

"It was definitely legal," said Cohen, "but they used a loophole in the law to take advantage of people."

What the company did was not an isolated case.

"Donald Trump is no worse than the other vitamin hawkers out there," said Ferraro.

The Urine Test

There are two elements of The Trump Network products that nutritionists question.

The first is the at-home urine test.

The Trump Network promoted the PrivaTest as a way to develop a personalized vitamin regimen.

The test, along with the first month's supply of vitamins, cost $140. It was recommended the PrivaTest be administered every six months for an additional cost of $100 for each retest.

Under the program, a consumer would collect a urine sample at home and mail it into a lab, which would then analyze it to determine what vitamins the person needed.

The PrivaTest is now listed as part of the MyVitaminsRx section of the website for Bioceutica, the company that purchased The Trump Network assets for an undisclosed amount in 2012.

Officials at the Trump for President campaign and executives at Bioceutica did not respond to requests from Healthline for an interview for this story.

Trump has said he was not involved in the manufacture or distribution of the products that were developed by a company called Ideal Health. He simply licensed his name and brand.

However, the presidential candidate recorded an online video, posted a letter online, and spoke at two conventions promoting the products.

For a story on its website, The Daily Beast interviewed a doctor who worked at The Trump Network. The unnamed doctor produced a 12-page document that he said proved the validity of PrivaTest.

However, The Daily Beast reported the papers failed to mention a single test done on humans. It also was never published in any peer review medical journal.

On its website, Bioceutica states the PrivaTest, "provides an accurate, scientific measure of critical metabolic markers in your natural waste fluids ... to determine the status of your nutritional health."

Four nutrition experts interviewed by Healthline found that claim difficult to believe.

Hermes said deficiencies in vitamins B12 and D can be evaluated with urine tests.

However, she told Healthline those findings require, "multiple samples to be taken over narrow time windows and over long periods of time, not a one-off collection or monitored every six months like the PrivaTest."

She added that a physician should oversee those test and they should not be done at home.

"There is not a urine test that can be used to design a targeted vitamin that will offer any proven health benefit," she said.

Dr. Steven Heymsfield, a professor in the metabolism/body composition laboratory at Louisiana State University's Pennington Biomedical Research Center, agreed.

He told Healthline that vitamin deficiencies, on rare occasions, can be detected via urine samples, but they involve specialized tests in labs.

"The idea that a urine test can be used to dose a vitamin supplement is likely specious and we would need to see their documentation to support such a claim and product," Heymsfield said.

"This is fanciful marketing," added Cohen. "It completely comes out of thin air."

Cohen added that a company could make far more money off a groundbreaking urine test such as PrivaTest than it can selling vitamins.

That leads him to believe the test isn't what it's purported to be.

The Vitamins

Nutrition experts tend to agree that the vast majority of Americans don't need to take vitamins or other supplements.

In fact, a study done between 2003 and 2006 concluded that only 10 percent of Americans have vitamin deficiencies.

Most nutritionists say people can obtain sufficient vitamin levels by eating a balanced diet.

Nonetheless, The Trump Network hailed their product as a way for people to improve their "health and wellness."

On its website, Bioceutica states their Custom Essential vitamins "are custom formulated vitamins, chelated minerals, amino acids and phytonutrients that uniquely target your body's needs."

The specific ingredients for the vitamins are not listed. They don't have to be under FDA regulations.

The doctor who spoke to The Daily Beast still had a bottle of the original Trump Network vitamins. He told them the bottle had words on it such as "high grade comprehensive multivitamin," "mineral antioxidants," "liver inflammation," and "detox support."

Cohen said this is typical "mumbo jumbo" used by some vitamin manufacturers to make their product sound legitimate.

Ferraro agreed.

"They use terms that in essence mean nothing," she said.

Heymsfield added the vague nature of vitamin labels makes it difficult to ascertain their effectiveness.

"The claims we have to work with, such as 'detox,' do not provide us any clue as what was included in the product," he said. "The question then is what vitamins were in the product, who manufactured them and what tests were done to assure their purity."

Besides not providing any healthful benefits, the nutrition experts said these vitamin products have the potential to do some harm.

A 2015 study published in The New England Journal of Medicine concluded there are 23,000 emergency department visits in the United States every year connected to "adverse events" involving dietary supplements.

Those include cardiac problems as well as problems from swallowing pills, especially with children and older adults.

"Taking too many vitamins can absolutely cause harm," said Hermes. "There have been cases of people accidentally overdosing on vitamins because the products contained huge quantities of certain vitamins or minerals, which was not reflected on the product label."

"The FDA and FTC have warned that some over-the-counter products may not always have the ingredients they are reported to contain," added Heymsfield. "That's why quality control is so important and credible manufacturers always do that for their products."

That's why, the nutrition experts say, consumers should do their homework before buying vitamins, especially if they are mail ordering them.

"Perhaps a good litmus test for the consumer would be to avoid products that make any kind of health claim, especially ones that seem too good to be true," said Hermes.