Is Fat Bad and Can Low Fat Diets Cause Depression?
A reader wrote on Facebook that she was on a diet and was feeling depressed. Although she admits to losing weight, she felt that her mornings were no longer met with enthusiasm and wondered if it could be her new food choices.
She started a, what I call, “home-made diet,” mostly all salad. This reader completely eliminated all fats — even those found in nuts. She admits to drinking wine at night to “feel better.” I asked Dr. David Edelson, an Assistant Clinical Professor of Medicine at Albert Einstein College of Medicine and former director of the Weight Management Clinic at North Shore-LIJ Medical Center, if low fat diets can cause depression. Here’s what he advised:
Research seems to indicate that low fat diets can cause depression. A recent article in the British Journal of Nutrition followed 20 individuals on two diets, one with 40% of calories from fat and one that started with 40% fat and after one month, switched to a diet with only 25% calories from fat. The latter group showed a 25% increase in depression and hostility from baseline.
It seems logical that too low a fat intake can affect both normal hormone production (through lowered cholesterol intake) as well as possible nerve and cell membrane repair that comes from healthy fat sources. Either of these could lead to the findings seen by these researchers. Omega-3 fats are vital to our health, both physical and mental.
Is fat bad?
Dietary fat is essential for life. Our bodies use fat to produce a huge variety of tissues and hormones including:
- Cell membranes: virtually every cell in our body has an outer layer produced from phospholipids, a derivative of fat. Without fat, the wall of the cell would collapse and the cell disintegrate.
- Myelin (nerve) sheath: the coating on nerve and brain tissue is composed of 80% fat. Without it, the nerves would not be able to talk to each other, and diseases such as Multiple Sclerosis develop.
- Hormones: virtually every hormone produced in your body starts out from the cholesterol molecule. The body uses this form of fat as the building block for estrogen, testosterone, cortisol, progesterone, and many other essential hormones required for normal body function.
What is the recommended daily allowance of fat?
This depends on the individual in question, as there is no single diet that works for every person. It also depends on the TYPE of fat being consumed. Bad fats (saturated and trans-fats) should be kept to an absolute minimum (less than 5% of daily calories.) But good fats (Omega-3’s, Mono-unsaturated fats) should be consumed with gusto, especially in individuals with diabetes, metabolic syndrome or any condition associated with insulin resistance. In these individuals we often increase healthy fat intake to 30-40% of daily caloric intake.
ABOUT DR. DAVID G. EDELSON
Dr. Edelson is the founder and medical director of HealthBridge, a nationally recognized preventive health facility. Dr. Edelson is widely recognized as one of the nation’s top weight loss experts. He is board certified in both Internal Medicine and Bariatric Medicine, and is a two-time recipient of the Faculty Teaching Award at North Shore/LIJ Medical Center. Dr. Edelson has been a featured speaker on Obesity Management for Medical Grand Rounds at some of the top hospitals in the country. He has published independent research in the Journal of the American Diabetes Association, Nutrition, and has been featured in articles in The New York Times, Woman’s Day, and Essence, among many others.