Lipids are a class of substances that include dietary fat and internal and dietary cholesterol. You need these substances to maintain certain aspects of your health, and if your levels of lipids and lipid byproducts fall too low, you can develop serious health problems, including essential fatty acid deficiencies and a low cholesterol condition called hypolipidemia.
You need a certain amount of fat in your diet to supply your body with substances called essential fatty acids. Bodily functions that rely on the presence of these acids include brain development, normal clotting of your blood and regulation of potentially dangerous inflammation. You also need fat to absorb and use vitamins A, D, E and K. Cholesterol helps form all of the cells in your body. It also helps you produce vital substances called hormones and protect the nerves that carry signals to and from your brain.
Essential Fatty Acid Deficiency
The essential fatty acids you need to maintain your health are called linolenic acid, or alpha-linolenic acid, and linoleic acid. Alpha-linolenic acid belongs to a class of substances called omega-3 fatty acids, while linoleic acid belongs to a class of substances called omega-6 fatty acids. The typical American diet contains considerably more omega-6 acids than omega-3s, according to Oregon State University's Linus Pauling Institute. If you don't get enough of both of these types of acids, you can develop symptoms that include poor healing of wounds, heightened susceptibility to infection and a scaly, dry rash on your skin. Infants and children who don't get enough of these acids can experience abnormally slow rates of growth.
Hypolipidemia occurs when your blood levels of normally harmful LDL cholesterol fall below 50 mg/dL, or when your blood levels of total cholesterol fall below 120 mg/dL. In addition to LDL, total cholesterol readings include your blood levels of beneficial HDL cholesterol and another form of normally harmful cholesterol called VLDL cholesterol. Some people develop a form of hypolipidemia called primary hypolipidemia, which stems from genetic abnormalities. However, most people develop a form of the disorder called secondary hypolipidemia, which can stem from health problems that include nutrient malabsorption, malnutrition, chronic infection, an overactive thyroid gland and cancers of the blood.
The risks from secondary hypolipidemia are typically the same as those associated with its underlying causes, the "Merck Manual for Healthcare Professionals" reports. People with certain forms of primary hypolipidemia may not have enough LDL and VLDL in their bloodstreams to transport sufficient amounts of vitamin E; if this is the case, severe vitamin E deficiency can trigger symptoms that include nerve damage, degeneration of the retinas in the eyes, brain damage and death. Infants with another form of primary hypolipidemia can develop problems that include lack of normal fat absorption, nerve damage and a general inability to thrive. Consult your doctor for more information about adequate lipid levels and the potential risks associated with abnormally low lipid levels.
- American Association for Clinical Chemistry - Lab Tests Online: Lipid Profile
- Oregon State University - Linus Pauling Institute: Essential Fatty Acids; Jane Higdon, Ph.D.; December 2005
- "Merck Manual for Healthcare Professionals": Hypolipidemia
- Harvard Health Publications - Harvard Medical School: Which Cholesterol Test Should You Get?; November 2004