Excerpt from Dr. Feder's, Natural Baby and Childcare

Hydrogenated fat is made when a high-pressure hydrogen mixes with an unsaturated fat. This chemically processed fat also contains trans fatty acids, which raise LDL (bad cholesterol) levels and lower HDL (good cholesterol). In addition, the trans fatty acids may be linked to obesity, diabetes, immune system conditions, and sexual dysfunction in men, including low testosterone, abnormal sperm production, and prostate disease.

These unhealthy hydrogenated, partially hydrogenated, and trans fats are found in most processed foods, such as donuts, potato chips, French fries, candy bars, peanut butter (except the natural varieties), salad dressings, cereals, cookies, crackers, shortening, pretzels, and fried foods. Like sugar, the taste of trans fats can be "addictive." Moreover, we often eat trans fatty foods without even knowing it, thinking we have opted for the healthy, "low-fat" option. Be sure to read the fine print on the nutrition label. Don't buy them! They last longer on the store shelf, are less expensive than saturated fat, and to many palates they taste good. But the long-term effects are not worth the short-term gratification.