The Scoop on Low-Fat Diets

January 7, 2015 Updated: January 7, 2015

Many people discussing their diet plans think in terms of low-fat options as a way to shed those unwanted pounds.  There are so many misconceptions around the role of fat in weight loss that I thought it would be helpful to share some of my understanding of the current state of affairs around low fat diets.

Many processed foods, which we should try to avoid, nonetheless, often have added sugar to make up for the loss of flavor from limiting fat content.  What many people do not realize is that adding any kind of sugar or sugar substitute to food can increase our sweet cravings.  That is not a direction we want to go in especially when looking to manage our weight and general health.

There are so many healthy fats available that when consumed in moderation actually can help us to feel satiated so that in the long-run we actually lose weight.  That is one of the benefits of fat in our diet – to help us feel full.  Studies comparing low-fat diets to those with added healthy fats have found more weight loss and the ability to keep the weight off over time in the healthy fat group.  I remember similar studies from many years ago and we have to come to a place to finally believe in the health benefits of at least some fats.

Not all fats are equal in terms of health benefits.  Care needs to be given to avoiding liquid vegetable fats, such as canola, safflower, and corn oils, which when heated to smoke-point result in the formation of free radicals that can be damaging to the body and lead to disease over time.  Many of theses oils are processed and do not have the same health benefits of extra virgin olive and coconut oils, and avocados.

Artificial transfats are formed when hydrogen is added to oils to make them solid, and are not healthy fats. They are used for taste, texture, and to increase shelf life of certain foods, such as baked goods, frozen pizza, and stick margarine.  They can cause inflammation in the body, which is now believed to be at the heart of many diseases.  Saturated fats in in meat, especially from animals that have been grass-fed,  can be consumed in moderation for most people unless otherwise not recommended under the care of a physician.

Dietary fat is beneficial in many ways.  It enables the body to absorb fat-soluble vitamins A, D, E, and K, and therefore, low-fat diets would not be recommended on this count alone. Dietary fat also is needed to make our tissues and manufacture chemicals in the body.  Fats provide us with energy, and are needed to form our cell membranes and provide insulation to the body, which provides cushioning to the organs and prevents heat loss.  Adequately formed cell membranes are especially important in allowing nutrients to enter our cells and to let out any cellular waste products.

Dietary fat also is a crucial part of our myelin sheath that provides insulation to nerve cells and speeds up nerve impulse conduction throughout the body. Our brain is approximately sixty percent fat.  Should fat intake be too restricted, it has the potential to compromise cognitive function, such as short and long-term memory.

Interestingly, when we consume fat, it is broken down in the body as triglycerides, but as these levels increase in the liver and bloodstream, the body counteracts them by no longer producing its own triglycerides.  It is a built-in balancing mechanism against excess triglyceride intake.  Dr. William Davis, in his book, Wheat Bellies, reports at the “net effect of high fat intake is little or no change in triglyceride levels.”

Another interesting finding cited by Dr. Davis is that carbohydrate consumption stimulates insulin production to clear away excess sugar in the blood, which in turn triggers fatty acid synthesis in the liver.  As a result of fatty acid synthesis, our blood is flooded with triglycerides.  The same balancing mechanism to the intake of dietary fats does not come into play here.

The moral of the story is that consumption of healthy fats in moderation appears to keep our bodies running efficiently, and can play a major role in weight loss and sustaining results over time. Excess intake of simple carbohydrates in the way of grains, pasta, bread, and pastries, all eventually increase triglyceride levels, which in turn have been associated with possible hardening and thickening of our arteries.  Once blood flow is blocked, there is an increase our risk of stroke, heart attack, and heart disease.  High triglycerides also has been associated with increased risk of diabetes, high blood pressure, and obesity.    These possibilities should make us think twice before reaching for the bread basket and processed foods. Whole grains have health benefits, but should be consumed in moderation.  Hopefully, some food for thought.