The Skinny on Fats – health experts keep changing the story
Marcia Zimmerman, M.Ed., CN
Health experts keep changing the story on fats. First we were told that polyunsaturated fats were better than saturated fats. Then it was discovered that refined polyunsaturates were favorite targets for free-radical attack. Next, monounsaturated fats took center stage and have remained in the spotlight ever since. The Mediterranean Diet, with its high intake of olive and other oils high in monounsaturates, offers several important safeguards against cardiovascular disease, cancer and overall mortality. (1) While monounsaturated fats are important for maintaining optimum health and smooth supple skin, it’s the kind of fatty acids and antioxidants they contain that make up the real story.
Dark green unrefined “extra virgin” olive oil has a delightful full-bodied flavor due to its natural antioxidants. Not only are the oils of various olive cultivars distinctive, they all help fight arterial plaque buildup. (2) Olive oil has a long history in Europe as both food and medicine, and carbon dating of seeds found in Spain have shown that the use of olive oil dates back 8,000 years. Gourmet chefs usually prefer particular oils for various uses in making dressings, marinades, and sauces for dipping. Olive orchards have now achieved a status second only to that of vineyards.
Macadamia nut oil is another designer oil that is fast gaining a reputation among chefs and health experts. The nuts originated in Australia where they were staples in the diets of the Aborigines. In 1881, they were introduced in Hawaii and in the 20th century, made their way to California where several cultivars are now grown. Like olive oil, macadamia nut oil is rich in antioxidants and contains the highest levels, greater than 80 percent monounsaturates, primarily palmitoleic (omega-7) than other oils. (3)
Macadamia nut oil products found in mass market are typically refined, with many of the antioxidants removed. The highest levels of antioxidants in macadamia nuts are found in the shells. During cold processing, some of these antioxidants leech into the oil, increasing its antioxidant potential. (4) Unrefined and organic oils have a golden colour, pleasing nutty aroma and buttery flavour. Scientists have found that macadamia nut oil lowers LDL cholesterol and triglycerides, and may help prevent stroke. (5) It is delightful on vegetables, in soups, on popcorn, and as a replacement for butter in baking.
The essential oils (fish oils, flaxseed, GLA, DHA), which are available as liquids and packaged in black bottles, must be stored in the refrigerator even when they have not been opened. You cannot heat or cook with them. Essential fatty acid supplements are convenient to take and have specific therapeutic value.
Cardiovascular and Nerves - Consumers have been advised to eat more fish rich in Omega-3 to reduce their risk of cardiovascular disease. However, experts worry that eating several servings of fish each week may not be safe especially during pregnancy, nursing or trying to conceive. Instead they recommend fish oil supplements such as Omega-3 from algae, Fish Oil, and Omega-6 from Evening Primrose and Borage oils. (6)
Anti-allergenic and Skin - Gamma linolenic acid (GLA) is an omega-6 fatty acid with anti-inflammatory and blood lipid lowering potential. Moreover, it reduces platelet stickiness and prevents the growth and proliferation of cancer cells. (7) Effective doses appear to be three grams of Omega-3, and 2 grams of GLA.
Pain Relief - A blend of cetylated fatty acids including myristate, myristoleate, laurate, oleate, palmitate and palmitoleate appear to be effective in reducing inflammation and pain in arthritis and other inflammatory conditions. (8) In a San Diego California study of sixty-four patients with osteoarthritis, an oral preparation of cetylated fatty acids known as Celadrin significantly improved range of motion and flexibility.
Two other studies on osteoarthritis patients at the University of Connecticut, using a topical preparation of Celadrin, showed significantly greater knee stability, improvement in stair climbing ability, balance and strength, and reduction of pain. (9)
Animal studies at the University of Minnesota have shown that cetylated fatty acids administered either topically or orally are well tolerated and rapidly dispersed throughout the body. (10) Doses for the oral form are 1500 mg three times a day. The topical cream is applied two to four times a day.
Enjoy Some Nuts Every Day
Although high in fat, nuts contain oils that reduce the risk of coronary heart disease. Nuts also contain potentially cardio protective components including phytosterols, tocopherols and squalene. Walnuts, almonds, pecans, Brazil nuts and macadamia nuts were all found to be good sources of these compounds. (11) Diets that included one or two servings of macadamia nuts a day have been shown in studies done in Brisbane, Australia and Honolulu, Hawaii to improve blood lipid profiles as effectively as low-fat, complex carbohydrate diets. (12), (13), (14) Furthermore, scientists at the Harvard School of Public Health found that eating nuts and peanut butter reduced the risk of type II diabetes in women. The researchers suggest that nuts might replace refined grain products, and red or processed meats in order to not increase caloric intake. (15)
The Lowly Goober Gets New Respect
Americans eat more peanuts and peanut butter than all other nuts combined. (16) A Pennsylvania State University study of 13,000 men, women and children revealed that peanut eaters had higher intakes of several hard-to-get nutrients compared to those who did not consume peanuts. Peanut butter and peanut eaters had increased levels of vitamin A, vitamin E, folate, calcium, magnesium, zinc, iron and phytonutrients resveratrol, beta-sitosterol and p-courmaric acid. What’s more, peanut eaters also had leaner bodies than non-peanut eaters. (17) This study helps to dispel the myth that higher-fat foods automatically lead to weight gain.
The Peanut Butter Diet evolved from studies such as this that showed the benefits of eating peanuts and peanut butter, particularly their high satiety factor. In one small study, ten health workers aged fifty-plus, consumed 1500-calorie healthy and moderate fat (35%) diet that included two tablespoons of peanut butter eaten twice a day. The women had at least one cardiovascular risk factor - high blood pressure, altered blood lipids or diabetes. Peanut butter was chosen because previous studies at Harvard/Brigham Women's Hospital had shown that over an eighteen-month period, three times as many women stuck with a diet that included peanut butter or peanuts, (McManus) because of a hunger curbing effect. (18), (19)
Peanuts contain about 2 grams of fibre per tablespoon and when spread on two slices of whole-wheat bread, deliver six grams of fibre. Peanut butter makes some yummy sauces. The barbequed ribs a group of scientists and I prepared during a recent weekend at the Culinary Institute of America Greystone in California’s Napa Valley were the best I have ever eaten.
This term refers to coconut, palm kernel and palm oils. These oils contain a variety of fatty acids, but unlike olive, macadamia and peanut oils, which contain high levels of unsaturated fatty acids and are liquid at room temperature, tropical oils have high levels of saturated fats and are solid at room temperature. They are gaining popularity as food manufacturers push to replace hydrogenated oils that contain trans fats. The latest hoopla over coconut oil has been its inclusion in weight loss regimens. Two books featuring coconut products have hit bestseller lists. (20) Moderate increase of tropical oils including coconut and palm appear to improve blood lipid profile, largely because of their high lauric acid content. (21)
The health benefits of medium chain triglycerides (MCTs) such as caprylic and lauric have been known for some time. Lauric acid has been found to improve blood lipids and red palm oil is rich in antioxidants such as beta-carotene and tocotrienols, the vitamin E active constituent. (21), (22), (23), (24) However, there is concern among some experts that eating too many saturated fats, including the tropical oils used to make trans fat free margarine and shortening, can have deleterious effects on cardiovascular health.
In addition, there are differences in processing palm and palm kernel oils that make some choices unhealthy. According to Dr. Andrew Weil palm oil is a better choice than palm kernel oil because chemical solvents are needed to extract palm kernel oil while none are required to press the oil from palm fruit. Fractionation is used to processes palm and palm kernel oil and eliminates many of their natural antioxidants, which makes them the least desirable of the tropical oils. (25) It seems prudent to check ingredient labels for fractionated palm kernel oil and avoid it. Best of all, look for NOW organic coconut oil that has an impressive resume for boosting immunity. It also a distinctive flavour to foods prepared with an East Indian theme.
1. Charlene Laino, Mediterranean Diet Lowers C-Reactive Protein Levels Medscape Medical News 11/19/03
2. F Visioli; C Galli; Antiatherogenic Components of Olive Oil Curr Atheroscler Rep 2001;3:64-67.
3. J Hiraoka-Yamamoto; et al; Serum Lipid Effects of a Monounsaturated (Palmitoleic) Fatty Acid-Rich Diet Based on Macadamia Nuts in Healthy, Young Japanese Women Clin Exp Pharmacol Physiol 2004;31 Suppl 2:S37-8.
4. LA Quinn; HH Tang; Antioxidant Properties of Phenolic Compounds in Macadamia Nuts AOCS 1996;73:1585-1588.
5. Y Yamori; et al; Dietary Prevention Of Stroke And Its Mechanisms In Stroke-Prone Spontaneously Hypertensive Rats- Preventive Effect Of Dietary Fibre And Palmitoleic Acid J Hypertens Suppl. 1986;4:S449-52.
6. Laurie Barclay; Fish Oil Supplements May be Safer Than Eating Fish Medscape Health News, 1/28/05
7. Thorne Research (no author listed); Gamma-Linolenic Acid (GLA) Monograph Alternative Medicine Review 2004; 9:70-78.
8. Lorna R Vanderhaeghe; Get a Grip on Arthritis Mississauga, ON Bearing Marketing Communications, Ltd.,2004 pp 16-20.
9. William Kraemer; et al; Effects of Treatment With a Cetylated Fatty Acid Topical Cream on Static Postural Stability and Plantar Pressure Distribution in Patients with Knee Osteoarthritis Journal of Strength and Conditioning Research 2005; 19:115-121.
10. William Kraemer; et al; A Cetylated Fatty Acid Topical Cream with Menthol Reduces Pain and Improves Functional Performance in Patients with Arthritis Journal of Strength and Conditioning Research (in press).
11. LS Maguire; et al; Fatty Acid Profile, Tocopherol, Squalene And Phytosterol Content Of Walnuts, Almonds, Peanuts, Hazelnuts And The Macadamia Nut Intnl J Food Sci Nutr 2004;55:171-178(8).
12. D Colquhoun; et al; Comparison Of A High Mono-Unsaturated Fatty Acid Diet (Enriched With Macadamia Nuts) And A High Carbohydrate Diet On Blood Lipids Wesley Hospital, Brisbane Australia, May 1992.
13. JD Curb; et al; Serum Lipid Effects Of A High-Monounsaturated Fat Diet Based On Macadamia Nuts Arch Intern Med 2000;160:115408.
14. ML Garg; et al; Macadamia Nut Consumption Lowers Plasma Total And LDL Cholesterol Levels In Hypercholesterolemic Men J Nutr 2003;133:1060-3.
15. R Jiang; et al; Nut and Peanut Butter Consumption and Risk of Type 2 Diabetes in Women JAMA 2002;288:2554-60.
16. C Alper and R Mattes; Peanut Consumption Improves Indices of Cardiovascular Disease Risk in Healthy Adults J Amer Col Nutr; 2003;22:133-141.
17. Amy Griel; et al; Improved Diet Quality with Peanut Consumption J Amer Col Nutr; 2004;23:660-668.
18. C Alper and R Mattes; Peanut Consumption Improves Indices of Cardiovascular Disease Risk in Healthy Adults J Amer Col Nutr; 2003;22:133-141.
19. SV Kirkmeyer and Richard Mattes; Effects Of Food Attributes On Hunger And Food Intake Intnl J Obesity 2000:24:1167-1175.
20. Fife B, Kabara J; The Coconut Miracle, Avery, 2004.
21. Nicole de Roos; et al; Consumption of a Solid Fat Rich in Lauric Acid Results in a More Favorable Serum Lipid Profile in Healthy Men and Women than Consumption of a Solid Fat Rich in trans-Fatty Acids J Nutr 2001;131:242-245.
22. DO Edem Palm Oil: Biochemical, Physiological, Nutritional, Hematological, and Toxicological Aspects: A Review Plant Foods Hum Nutr 2002;57:319-41.
23. CE Elson; Tropical Oils: Nutritional and Scientific Issues Crit Rev Food Sci Nutr 1992;31:79-102.
24. S Park; et al; Relative Effects of High Saturated Fatty Acid Levels in Meat, Dairy Products, and Tropical Oils on Serum Lipoproteins and Low-Density Lipoprotein Degradation by Mononuclear Cells in Healthy Males Metabolism 1996;45:550-8.
25. Online information, from Dr. Andrew Weil (drweil.com)