The following information comes mostly from Mary Enig's article, Oiling of America, as at http://www.westonaprice.org/knowyourfats/oiling.html and http://www.drcranton.com/nutrition/oiling.htm . Mary Enig's website is at http://lauric.org .
- Cholesterol and saturated fats are good fats. Hydrogenated oils and rancid oils or fats are bad fats.
BAD FATS - HYDROGENATED OILS [in COOKING OILS] etc
- Most transfats are from partly hydrogenated vegetable oils, vegetable shortening and margarine, found in many processed foods. Natural transfats as in dairy are good. Hexane, one of the main hydrocarbons in gasoline, is used to make hydrogenated oil. Little, if any, hexane remains in the finished product, but it destroys virtually all nutrients in the oil, like vitamins. When these hydrogenated oil products first came out, doctors were concerned that they might lead to heart disease and cancer. These concerns were confirmed by research. Other problems have also been confirmed, though the media ignores these findings, due to food industry pressure. Following are confirmed problems caused by processed transfat consumption, along with source references.
- Hydrogenated oil does the following:
Reduces milk supply in breastfeeding women – 44.
Increases diabetes – 44.
Increases osteoporosis [brittle bones] – 45.
Lowers testosterone [mostly male hormone] – 45.
Lowers normal sperm count [making men infertile] – 45.
Changes gestation [fetal development] – 45.
Lowers birth weight – 46.
Lowers prostaglandins [hormone-like nutrients for muscle and blood vessel control] – 47.
Increases heart disease – 48, 53.
Increases breast cancer – 49.
Increases coronary heart disease [especially from margarine] – 50.
Fat in deep fried foods is up to 50% transfat – 51.
Increases cancer [from margarine & vegetable shortening] – 52.
Average consumption is at least 12 grams per day.
4 donuts or 6 cookies contain 30 grams.
One 10 oz. Bag of chips contains 46 grams.

GOOD FATS - SATURATED FAT
Following are listed the benefits of saturated fats in the diet,
i.e. tallow [beef fat], lard [pork fat], butter, palm oil, coconut oil, meat, etc:
Improves immune system [to fight infections, colds etc] – 54.
Improves bones – 55.
Increases cell energy & improves cell structure – 56.
Protects the liver – 57.
Helps utilize essential fatty acids – 58.
Reduces need for cholesterol – 59.
Improves the heart – 59.
Does not irritate artery walls.
Reduces need for stored anti-oxidants.
Helps prevent cancer.

GOOD FATS - NATURAL CHOLESTEROL
Following are some of the benefits of natural cholesterol:
Makes hormones that reduce stress.
Makes hormones that protect from heart disease and cancer.
Makes sex hormones for fertility and emotional balance.
Makes vitamin D for bones, nervous system, growth, mineral metabolism, muscle tone, insulin, reproduction, immune system, bile salts for digestion of fat.
Is an anti-oxidant to protect tissues from damage to prevent heart disease and cancer.
Is a repair substance for arteries - 60.
Increases serotonin in brain to make good feelings.
Reduces aggression, violence, depression, suicidal tendencies.
Cholesterol in breast milk greatly improves infants' brain development – 61.
Repairs intestinal walls.
Vegetarians tend to get leaky gut syndrome and other problems without cholesterol from animal products.
Shortage of fat and cholesterol in the diet produces nocturnal habits, fantasies, fetishes, bingeing, splurging, etc – 62.

References.
- 44. B B Teter, et al, "Milk Fat Depression in C57B1/6J Mice Consuming Partially Hydrogenated Fat," Journal of Nutrition, 1990, 120:818-824; Barnard, et al, "Dietary Trans Fatty Acids Modulate Erythrocyte Membrane Fatty Acid Composition and Insulin Binding in Monkeys," Journal of Nutritional Biochemistry, 1990, 1:190-195
- 45. T Hanis, et al, "Effects of Dietary Trans Fatty Acids on Reproductive Perforamnce of Wistar Rats," British Journal of Nutrition, 1989, 61:519-529
- 46. B Koletzko and J Muller, "Cis- and Trans-Isomeric Fatty Acids in Polasma Lipids of Newborn Infants and Their Mothers," Biology of the Neonate, 1990, 57:172-178
- 47. D Horrobin, "The Regulation of Prostaglandin Biosynthesis by Manipultion of Essential Fatty Acid Metabolism," Reviews in Pure and Applied Pharmacological Sciences, 1983, 4:339-383
- 48. G V Mann, "Metabolic Consequences of Dietary Trans Fatty Acids," The Lancet, 1994, 343:1268-1271
- 49. L Kohlmeier, et al, "Stores of Trans Fatty Acids and Breast Cancer Risk, "Am J Clin Nutr, 1995, 61:896;A25
- 50. R P Mensink and M Katan, "Effect of Dietary Trans Fatty Acids on High-Density and Low-Density Lipoprotein Cholesterol Levels in Healthy Subjects," N Eng J Med, 1990, 323:439-445
- 51. M G Enig, et al, "Isomeric Trans Fatty Acids in the U.S. Diet," J Am Coll Nutr, 1990, 9:471-486
- 52. W C Willett, et al, "Consumption of Trans-Fatty Acids in Relation to Risk of Coronary Heart Disease Among Women," Society for Epidemiology Research, June 1992, Annual Meeting, Abstract 249
- 53. W C Willett, et al, "Intake of Trans Fatty Acids and Risk of Coronary Heart Disease Among Women," Lancet, 1993, 341:581-585
- 54. J J Kabara, The Pharmacological Effects of Lipids, J J Kabara, ed, The American Oil Chemists' Society, Champaign, IL, 1978, 1-14; L A Cohen, et al, J Natl Cancer Inst, 1986, 77:43
- 55. B A Watkins, et al, "Importance of Vitamin E in Bone Formation and in Chrondrocyte Function" Purdue University, Lafayette, IN, AOCS Proceedings, 1996; B A Watkins, and M F Seifert, "Food Lipids and Bone Health," Food Lipids and Health, R E McDonald and D B Min, eds, Marcel Dekker, Inc. New York, NY, p 101
- 56. J F Mead, et al, Lipids: Chemistry, Biochemistry and Nutrition, Plenum Press, 1986, New York
- 57. A A Nanji, et al, Gastroenterology, Aug 1995, 109(2):547-54; Y S Cha, and D S Sachan, J Am Coll Nutr, Aug 1994, 13(4):338-43
- 58. M L Garg, et al, The FASEB Journal, 1988, 2:(4):A852; R M Oliart Ros, et al, Meeting Abstracts, AOCS Proceedings, May 1998, p 7, Chicago, IL
- 59. L D Lawson and F Kummerow, "B-Oxidation of the Coenzyme A Esters of Vaccenic, Elaidic and Petroselaidic Acids by Rat Heart Mitochondria," Lipids, 1979, 14:501-503
- 60. E M Cranton and J P Frackelton, "Free Radical Pathology in Age-Associated Diseases: Treatment with EDTA Chelation, Nutrition and
Antioxidants," Journal of Holistic Medicine, Spring/Summer 1984, pp 6-37
- 61. H. Engleberg, "Low Serum Cholesterol and Suicide," Lancet, March 21, 1992, 339: 727-728
- 62. R B Alfin-Slater, and L Aftergood, "Lipids," Modern Nutrition in Health and Disease, 6th ed, 1980, R S Goodhart and M E Shils, eds, Lea and Febiger, Philadelphia, p 134