Quality Focus: The Laboratory Notebook

Answering important questions about quality.

By Robert Green

Our questions this month were all posed at the SupplySide West show, which was held at the end of September, beginning of October, in Las Vegas, NV. Each year we see increasing interest in quality issues, meaning we all must be doing something right. This month the questions focus on NLEA food label requirements, L-carnitine (and its evil side D-carnitine), selecting an appropriate lab and male sexual enhancement products.

Q. I’m preparing a label for a new protein shake product and was told I need to get the information to complete the “NLEA mandatory food label requirements.” Can you tell me what that is?

A. NLEA stands for the Nutrition Labeling and Education Act of 1990. Final regulations implementing NLEA were enacted in 1993. In short, NLEA mandates what nutritional information must be on product labels and specifies how that information must appear. It was designed to aid consumers in making healthy food choices, reduce consumer confusion and encourage manufacturers to improve product quality.

Generally products in conventional food form must comply with NLEA. The 14 mandatory nutrients and the order in which they must be listed are: calories, calories from fat, total fat, saturated fat, cholesterol, sodium, total carbohydrates, dietary fiber, sugars, protein, vitamin A, vitamin C, calcium and iron. Some of these mandatory items can be deleted under certain circumstances. In addition to mandatory nutrients, manufacturers may voluntarily choose to include several additional nutrients, including: calories from saturated fat, polyunsaturated fat, monounsaturated fat, potassium, soluble fiber, insoluble fiber, sugar alcohols, other carbohydrates, other vitamins and minerals for which Reference Daily Intakes (RDIs) have been established, and the percent of vitamin A as beta-carotene.

Like all good federal regulations, there are exceptions to the rules and rules to the exceptions. Analytical laboratories providing this service usually have a NLEA mandatory nutrient package and offer the voluntary items as additions.

Q. I have been asked to locate a supply of L-carnitine, and was told to be certain I did not get D-carnitine. Can you brief me on this product and explain the “L” and “D” issue?

A. L-carnitine is made in the body from the amino acids lysine and methionine. It plays an important role in fat metabolism and energy production. Carnitine was discovered in 1905 by two Russian scientists who found it in the muscle tissue of mammals. Legend has it that carnitine got its name from the Latin word “carnis,” meaning meat.

L-carnitine increases the use of fat as an energy source by transporting fatty acids into the mitochondria, where oxidation takes place and the fatty acids are used to release energy for body functions. Research has shown the use of L-carnitine in exercise, weight management and cardiovascular health.

Carnitine [3-hydroxy-4-trimethylammonium-butyrate], like many biologically active molecules, exists in two forms: L-carnitine and D-carnitine. These two forms or isomers are mirror images of each other. The L is short for levorotation (levo meaning “on the left side” in Latin) designating that the molecule rotates polarized light to the left. D stands for dextrorotation (dextro meaning “on the right side”) when the molecule rotates polarized light to the right. Most molecules in the human body are L forms. L-carnitine is safe and widespread in the human body, with high concentrations in the skeletal and heart muscle. On the other hand, the D form does not exist in nature. D-carnitine is a competitive inhibitor of L-carnitine, and may even be toxic.

For many years the only available manufacturing process consisted of the synthetic chemical production of DL-carnitine with the subsequent separation of the D and L isomers. As a result, the potential for the D form remaining in the final product existed. Now most L-carnitine is produced by fermentation in a process that eliminates the formation of the D form. We can certainly determine if your L-carnitine has any of the D form present, but frankly we do not see that as much of a problem.

Q. I was in the neighborhood so I stopped in to visit the analytical lab I use. While the reports I receive from the lab on metal testing state that the method used is ICP-MS, the lab did not have that instrument. When asked, I was told the lab sends all metal testing to another lab. Is this appropriate?

A. This practice is widespread, but we do not believe it is appropriate. The selection of an analytical lab is a very important and personal decision. As we have said in this column many times, a lab should not be selected blindly. There are no minimum requirements that must be met for a lab to conduct supplement analytical services, so the quality of labs varies widely from excellent to incompetent. The only way you can be sure you are getting what you pay for is to investigate a potential lab. You are deprived of this when your samples are actually going to a lab unbeknownst to you.

In our early days when we did not have a full complement of instrumentation we had a policy of never subcontracting work to another lab. Quite frankly, since we could not guarantee another lab would apply the same care, skill, timeliness and responsiveness we did not want to be responsible for another lab’s work. If a client wanted an analysis which we could not provide, we told the client up front and recommended another lab that the client could contact directly, and we never sought any compensation from the other lab.

Today labs run the gamut from full disclosure, disclosure in the firm’s standard terms that some samples may be subcontracted, to silence. At a minimum, we believe any lab subcontracting work has a duty to disclose that to the client. It would then be for the client to permit this or seek additional information on the second lab. We strongly believe that subcontracting without disclosure is sneaky and inappropriate.

Q. I am importing an herbal male sexual enhancement product and I would like to be certain it is indeed herbal and does not contain Viagra. Can this be done?

A. Absolutely. With the popularity of the relatively new pharmaceuticals designed to treat male erectile dysfunction, it didn’t take a genius to figure out that herbal alternatives to these pharmaceuticals could be big hits. There is nothing wrong with that, except when you cheat. There have indeed been instances where pharmaceuticals have been found in these formulations. Needless to say, this practice is illegal and dangerous.

To properly do the job you need to screen these products for the three known pharmaceuticals—tadalafil, vardenafil and sildenafil. Just testing for one does not adequately do the job. The analysis is conducted by HPLC and standards are available.NW