Separating Food Fact From Fiction

BY DONNA MCALEER

Susan Meacham Barely has time to say what she does for a living before the questions begin.

"So what about this high protein diet? Is it good for you?"

"Does echinacea really help colds?"

"Is green tea the best source of antioxidants?"

"Is St. John's Wort harmful in any way?"

As a registered dietitian and a nutrition researcher, Meacham is used to these kinds of queries from people who find out she has a professional's understanding of the myriad unresolved issues in the field of nutrition. She doesn't mind answering their questions when the answers are available; in fact she is pleased when people express an interest in her field.

"Food is fuel for the human body," says Meacham, who is the founding director of the new UNLV nutrition sciences program. "It's what we run on, but most people give more thought to the gas they put in their cars — the brand, the grade, the price — than they do to the fuel they put in their bodies."

Currently, Meacham says, most people are confused about the barrage of conflicting claims about vitamins, supplements, and herbal remedies and what each is supposed to do. Add to that all the claims about which fad diet will result in the greatest weight loss, and it's easy to understand why there's so much confusion.

"Eating what's good for you can seem like a complicated business if you believe all the marketing and media hype about the latest food fads," she says, adding that the growing public need to separate nutrition fact from fiction is one of the reasons UNLV started its program in nutrition sciences two years ago.

An apple a day is still good nutrition advice, according to Susan Meacham, director of UNLV's nutrition sciences program.

Part of the problem, Meacham says, is that people lack context for the information they receive about nutrition. For instance, despite some increase in awareness of nutrition matters in recent years — due in part to greater governmental regulation of the food manufacturing industry — many people still do not understand the bewildering array of facts listed on the labels of food containers. People often not only lack an understanding of what the information means, but they also haven't the foggiest idea of how it's generated.

Hence, a little background on how nutrition information is produced is helpful, says Meacham, who holds a doctorate in human nutrition and foods and has researched the subject at several universities, as well as for the U.S. Department of Agriculture.

She notes that nutrition facts labels are generated with a computer program that accesses detailed information on each ingredient's calorie, mineral, and vitamin content; the computer then summarizes the overall nutritional breakdown.

But how is the basic information gathered in the first place?

The answer is slowly and carefully, Meacham says, adding that the meticulous nature of nutrition research — and the resulting pace at which it is conducted — may also be contributing to the lagging public understanding of some nutrition matters.

"My field is a bit behind the curve. There is so much research yet to be done before we can really determine the effectiveness of various substances," says Meacham. For example, she points out, many of the herbal remedies that are currently on the market have yet to be analyzed properly in objective scientific studies.

When research on those substances is conducted, however, painstaking care will be taken in all aspects, particularly in the testing of human subjects and the effects of each dietary variable; after all, she points out, when you're dealing with people's health, attention to safety and well-being is of the utmost concern.

A look at one of Meacham's most recent studies illustrates how the research process works in her field — and how much attention to detail must be paid.

Many of Meacham's publications have focused on boron, a naturally occurring "ultra-trace" element. While it is not found in large quantities like the more well-known elements of calcium, iron, or potassium, it plays an important role in properly metabolizing other minerals, especially calcium. Meacham is interested in analyzing how the element relates to chronic diseases, including cancer, osteoporosis, and arthritis.

"We usually associate only calcium with bone density, but farmers have known for years that if you add boron as well as calcium to the soil, you get stronger, sturdier plants. The trick is to know the proper proportion," Meacham says.

She compares the calcium and boron interaction that produces human bone strength to mixing mortar. If the elements are combined in the right mix, the mortar will be strong and long lasting; if the mix is off, the mortar may crumble prematurely.

But what is the proper amount for a trace element like boron? Researchers must first establish how much of it exists in the typical American diet before they can suggest guidelines.

Meacham's most recent work, which was completed in collaboration with U.S. Department of Agriculture research biologist Curtiss Hunt, establishes benchmarks for 12 different minerals (aluminum, boron, calcium, copper, iron, manganese, magnesium, molybdenum, phosphorus, potassium, sodium, and zinc) found in foods common in the American diet. They have also estimated mineral intake in the following age groups: infants, toddlers, male and female adolescents, adults, and seniors.

In Meacham and Hunt's study, 234 foods, including milk, peanut butter, pizza, meatloaf, cheese, bread, blueberry muffins, spinach, popcorn, beans, and vanilla ice cream, were analyzed to determine the benchmarks.

The process they used for measuring the mineral levels was thorough and rigorous. First, each sample was blended and put into a solution. Then, three identically sized samples were removed from each of the 234 foods being analyzed. Since there are traces of boron and other minerals in glass, special test tubes were used; also, contact between the samples and metal was avoided at all times. Water for food preparation was distilled and deionized.

Once the food samples were properly prepared in triplicate, acids that mimic those released during digestion were put into the solutions. Then, each sample was analyzed by a process called "inductively coupled argon plasma emission spectroscopy," which measures the trace mineral levels.

"The data from this study establishes how much boron and other minerals the U.S. population ingests," she says. "It also provides technical information needed for the development of special diets to be tested in future studies."

These types of studies must be conducted before research on humans can even begin, she says, noting that one of the challenges in studying nutrition in people is creating a safe way to research a diet in humans.

"It would not be ethical to study a diet missing some essential element people need. Instead of studying what would happen on a deprivation diet, we study a mineral-depleted or mineral-supplemented diet," says Meacham, whose own work with human subjects has focused on female athletes and low-income women.

In the future, Meacham would like to do more research with minerals used in complementary or alternative medical therapies. She believes that some minerals hold promise as agents that are hostile to cancer cells; in fact, she thinks scientific scrutiny may in some cases support anecdotal claims. But until research is completed on the substances that have spawned these claims — as well as many others — she is concerned that marketing efforts, not nutritional facts, drive consumer decisions.

"We need to assist people so they can decide what's credible. Nutritionists want to help people make informed decisions," she says, adding that manufacturers of nutritional supplements have elaborate web sites and slick infomercials making grand nutritional claims with little or no supporting evidence.

"Products need to be evaluated independently by registered dietitians," Meacham says. "People need to make decisions based on science, not marketing. Nutrition needs more of a science base to strengthen its assertions and to examine alternatives."

That's where UNLV's new nutrition sciences program enters the picture, she adds.

The program is designed to teach students about the complex nutritional and health variables associated with food, she says, and will focus on the medical aspects of nutrition, including disease prevention and treating illness.

The program offers students the opportunity to major or minor in nutrition sciences, or, for those majoring in health sciences, to select nutrition as a focus area.

According to Meacham, the field of nutrition is closely tied to many other subjects, including biology, chemistry, nursing, kinesiology, and health education. There's a big dose of science, particularly chemistry, in the program, she says, but there is also an element of art to it. To be effective, dietitians must understand the blend of social and cultural factors that influence what people eat.

Professionals in the field work closely with patients, doctors, physical therapists, nurses, and pharmacists in a variety of settings, including hospitals, wellness centers, school districts, private practices, and health spas, says Meacham. She notes that there are ample job opportunities in the field.

Now that the program is under way, Meacham says the next step is to help its graduates seek professional credentials to become registered dietitians.

"Our students at UNLV will be well prepared to meet professional standards. Credentialing is very important in this field," Meacham says. "The initials R.D. behind someone's name indicate that person can offer medically appropriate nutritional advice."

Meacham says she is pleased to be directing a program that will produce graduates capable of guiding members of the Southern Nevada community in their decisions about nutrition.

"I was very excited to be a part of something new and growing," says Meacham, who joined the UNLV faculty in 1998. "It's a wonderful program, and one that is certainly needed."

As for providing some helpful nutrition tips, she says the average person can begin improving his/her nutrition quite simply.

"It turns out Mom was right," she says. "Eating five servings of fruits and vegetables a day is a great way to get many of the vitamins and minerals we need. So reach for the apple."