|Vol. 23, No. 02||February 1, 2001|
Cottonseed Corners the "Healthy Cooking Oil" Market
By RONDA WENDLER
Texas Medical Center News
With its longstanding record of lowering cholesterol and fighting cardiovascular disease, corn oil has been sliding off grocery store shelves and into the kitchens of health-conscious cooks for years. But corn oil's popularity may soon be upstaged, says Dr. John Radcliffe.
Dr. Radcliffe, a professor of nutrition and food science and registered dietitian at Texas Woman's University's Institute of Health Sciences in Houston, is the author of an article published recently in the journal Plant Foods for Human Nutrition, which suggests that cottonseed oil may be more effective than corn oil in lowering serum cholesterol levels. Corn oil has been recommended for years by the American Heart Association for patients on a cholesterol-lowering diet.
In comparing corn oil to cottonseed oil, Dr. Radcliffe and associates found that cottonseed oil lowered cholesterol levels 13 percent more than corn oil, and provided two-thirds more vitamin E in the diet than corn oil.
The irony is that for years, cottonseed oil - newly proven to be one of the healthiest oils around - has been an ingredient in foods not considered particularly healthy, such as potato chips, doughnuts, cookies and snack cakes. It also is found in salad dressings and marinades, margarines and whipped toppings.
"Most people have eaten cottonseed oil, but they didn't know it," Dr. Radcliffe said. "Food labeling laws allow cottonseed oil to be `masked' on food labels with verbage that reads `contains corn oil, cottonseed oil or soybean oil.' The type of oil used depends on availability, which varies with geographic regions and time of year," Dr. Radcliffe said.
Praised for its light, slightly nutty flavor and non-oily consistency, cottonseed oil is known in the food industry as "America's oldest oil," and has been part of the American diet since it was first refined in the 1860s.
Particularly good for frying, cottonseed oil has a high smoke point, meaning it won't start smoking until heated to a high temperature. The hotter the oil, the less time food needs to remain immersed, resulting in a light, non-greasy texture.
Several restaurants in Houston feature cottonseed oil prominently in their recipes, and one in particular - Felix Mexican Restaurant on Westheimer - uses it exclusively, citing superior taste. The Houston Press has awarded Felix "Mexican Restaurant of the Year" three years in a row.
Although it is used commercially in food processing and in restaurants, Houstonians must travel to west Texas to buy cottonseed oil.
"Walk into any grocery store in Lubbock and you'll find it," Dr. Radcliffe said. Today, the oil is available for individual sale only in areas where cotton is grown, but Dr. Radcliffe believes this will change as consumers become increasingly aware of its health benefits. "I'm sure it will be promoted, sought out, and made more available in the next few years," he predicted.
"Cooks and restauranteurs in the southern states where cotton grows have long valued cottonseed oil for its pleasant taste, but cottonseed oil is much more than a palate pleaser," Dr. Radcliffe said.
"Our discoveries about its cholesterol-lowering and vitamin E-raising qualities have the potential to dramatically boost cottonseed oil's popularity," he said.
That's a major feat, considering the overwhelming number of oils that line grocery store shelves today. A quick walk down the aisle can be confusing to the average consumer, who must choose between corn, olive, grapeseed, flax, canola, peanut, sesame and soybean oil, to name a few. With this dizzying array of choices, what's a shopper to do?
The "Skinny" on Fat
Understanding the skinny on fats and oils is the key to making an intelligent choice, Dr. Radcliffe said.
"Fat, which is composed predominantly of fatty acids, is found in every cooking oil, in equal amounts. But some fats are considered to be `good,' while others are `bad.' The key to healthy cooking is knowing how to differentiate between the two," he advised. The fatty acids in fats are either saturated or unsaturated.
Saturated fatty acids are the nutritional "bad guys" because they increase cholesterol levels, which can lead to heart disease. Although saturated fatty acids usually come from animals, oils derived from plants also contain small amounts of saturated fatty acids. Two tropical oils - coconut and palm kernel oil - are highly saturated, and should be avoided by those on cholesterol-lowering diets.
Unsaturated fatty acids are derived mostly from plants, and nearly all vegetable oils, with the exception of tropical oils, are unsaturated.
Unsaturated, or "good" fatty acids, are further broken down into two types - monounsaturated and polyunsaturated. Monounsaturated fatty acids are known to help reduce the level of LDL, the "bad" cholesterol. Olive, canola and peanut oil are the three most widely used oils that are high in monounsaturated fatty acids. Rice bran oil, widely used in Japan and available in some U.S. stores, also is high in monounsaturates and quite healthy, Dr. Radcliffe said.
Polyunsaturated fatty acids also are healthy and like monounsaturates, reduce LDL cholesterol. Safflower, soybean, corn, cottonseed and sesame oil are high in polyunsaturated fatty acids.
All oils contain a mix of saturated, monounsaturated and polyunsaturated fatty acids.
"The trick to choosing the healthiest oil is to select one that is high in mono or polyunsaturates, and then consider its other valuable components, such as vitamin E," Dr. Radcliffe said.
Cottonseed oil is an excellent choice, he advised, because it is high in polyunsaturates and vitamin E.
"The bottom line is that fats are a necessary part of our daily diets. They make foods palatable, and provide essential fatty acids and vitamins," Dr. Radcliffe said. "Consumers simply need to be knowledgeable about `good' versus `bad' fats."
Getting an "A" in Vitamin E
In addition to its cholesterol-lowering capabilities, cottonseed oil has the highest amount of vitamin E of any vegetable oil, with the exception of almond oil and wheat germ oil. But almond oil is very expensive and wheat germ oil has a prohibitively bitter taste, making cottonseed oil the rational choice for most consumers.
Vitamin E is thought to play a protective role against many diseases, including cardiovascular disease and prostate cancer. Recent research suggests it may help prevent memory loss, and Alzheimer's patients are usually placed on mega doses of vitamin E.
But getting enough vitamin E in a normal diet is not easy, said Dr. Radcliffe, especially since the recommended dietary allowance, or RDA, was recently doubled by the Institute of Medicine's food and nutrition board. The board now recommends 15 milligrams a day for everyone. One tablespoon of cottonseed oil contains five milligrams, or one-third the recommended dietary allowance, of vitamin E. Working at least one tablespoon into a daily diet should be relatively easy for most people, and will provide a valuable boost in their vitamin E intake," Dr. Radcliffe said.
Getting vitamin E from foods is difficult, he said, because very few foods are good sources of vitamin E.
"Almonds, anchovies, sweet potatoes, jicama and wheat germ are about it, but many people do not eat these on a daily basis. It's more practical to get vitamin E from healthy cooking oils," he said, "which find their way into a myriad of foods."
Most U.S. residents consume only about 40 percent of the RDA for vitamin E, and statistics from the Centers for Disease Control show African-Americans and Hispanics have particularly low vitamin E intakes.
Taking a multivitamin that contains vitamin E won't necessarily solve the problem, Dr. Radcliffe said, because most multivitamins contain synthetic vitamin E, which is chemically different than natural vitamin E.
The ideal scenario, he said, is to consume cottonseed oil as an ingredient in salad dressings, baked goods such as whole wheat bread and bran muffins, stir-fried vegetables and other dishes.
In addition to increasing the RDA for vitamin E, the Institute of Medicine recently changed the way vitamin E content is calculated in foods.
Prior to the release of the new recommended dietary allowances, the vitamin E content of a food was calculated based on the level of two vitamin E-bearing compounds found in most foods - alpha-tocopherol and gamma-tocopherol. However, the Institute of Medicine now states that only alpha-tocopherol can be used in determining the vitamin E content of foods.
"Those oils with high levels of gamma-tocopherol, especially soybean, are now known to have had their vitamin E content overestimated. The vitamin E count for cottonseed oil is virtually unchanged, however, because it has low levels of gamma-tocopherol," Dr. Radcliffe explained.
The cotton industry is happily embracing the recent findings. While cotton is still a principle raw material for the world's textile industry, its dominant position has been seriously eroded by synthetic fibers. In the United States, cotton counts today for about 35 percent of the materials processed in textile mills, compared to 80 percent before World War II.
"A new day is dawning for the cotton industry, thanks to the promising research about the benefits of cottonseed oil," said Robert McLendon, president of the National Cotton Council of America.
©2006 Texas Medical Center