How Low Can You Go? The Big Fat Truth about Low-Fat Diets
Here are six health risks you’re taking when you restrict your fat intake too far.
1. Poor Vitamin Absorption
Eating a diet too low in fat can interfere with the absorption of the fat-soluble vitamins A, D, E and K. Because these nutrients are fat soluble, your body needs dietary fat to utilize them. These vitamins are stored mostly in the liver and fat tissue and are important in bodily functions such as growth, immunity, cell repair and blood clotting. If you’re not eating enough fat to bring these vitamins into your body, they will be excreted, and you may be at risk for a vitamin deficiency.
A diet that’s too low in fat—especially essential fatty acids, which your body can only get from food—might hurt your mental health. Both omega-3s and omega-6s play roles in mood and behavior. They are the precursor to many hormones and chemicals produced in the brain. One study published in the Journal of Affective Disorders has linked low and abnormal essential fatty acid intake to depressive symptoms. Other research shows that, because fatty acids help to insulate nerve cells in the brain, allowing these nerve cells to better communicate with one another. People who are deficient in omega-3s may suffer from bipolar disorder, schizophrenia, eating disorders, and ADHD.
3. Increased Cancer Risk
Colon, breast, and prostate cancers have all been correlated with low intakes of essential fatty acids. Research has shown that a high intake of omega-3s slows prostate tumor and cancer cell growth, too. If your diet lacks healthy fats, you could be increasing your risk of cancer.
4. High Cholesterol and Heart Disease
Low-fat diets also play a role in cholesterol levels and heart disease. When your diet is too low in fat, your body’s level of HDL (the “good” cholesterol) goes down. This is problematic because you want your HDL level to be high to help protect against heart disease. HDL collects “bad” cholesterol from the blood and transports it to the liver for excretion. When those ratios are out of balance—and when your LDL (“bad” cholesterol) level gets too high, you face cholesterol problems and an increased risk of heart disease. Essential fatty acids, especially Omega-3s, can elevate HDL, improve cholesterol levels and protect the heart.
5. Imbalance of Nutrients—Especially Carbs
If you’re not eating enough fat, then you’re likely getting too much of other things, namely carbs and/or protein. This affects the overall balance of your diet, which could lead to health problems. A carbohydrate-rich diet can inflate appetite and girth and increases your chances of developing type 2 diabetes. On the flip side, a high-protein diet taxes the kidneys and liver and can lead to osteoporosis. Both cases can result in nutrient deficiencies. The key is to balance all three macronutrients—fat, carbs and protein—to ensure optimal nutrition and disease prevention (more on that below).
If you’re always choosing low-fat or fat-free foods at the grocery store, you could be shortchanging your weight-loss efforts. Many of these processed foods contain added sugars to enhance taste; often they’re similar in calories to the original full-fat product.
Foods such as avocados, canola and olive oil, almonds, tuna, salmon and flaxseed are all excellent sources of healthy fats. High-fat meats and dairy products, trans fats (hydrogenated oils), and saturated fats should be limited.