Palmitic acid is a saturated long-chain fatty acid (LCFA), a term for fatty acids containing 13 to 21 carbons. Palmitic acid contains 16 carbons. This acid is found in most fats and oils, such as soybean oil. It can also be found naturally in plants and animals and created in laboratories. Additionally, palmitic acid can be found in foods such as palm oil, butter, meat, milk, and cheese.
Soybean oil is commonly found throughout human food and has many other applications as well. One part of soybean oil is palmitic acid. Many think that lowering the palmitic acid in soybean oil would reduce the fatty acid in the oil and increase the oil’s quality, making it better for humans to eat.
The palmitic acid structure contains a 16-carbon backbone. The palmitic acid molecular formula contains C16H32O2, which is 16 carbon, 32 hydrogens, and 2 oxygen. Palmitic acid has a molecular weight of 256.42. It is commonly used in personal care products and cosmetics.
Palmitic acid has a bad reputation, primarily because it has been shown to have negative health effects. It has been linked to several conditions, including brain diseases and cancer. However, studies don't necessarily agree on this. Associations between palmitic oil and an increased risk of breast cancer were found in one study but not in another, for example.
Palmitic acid can also be observed in Escherichia coli, or E. coli, and an aged mouse’s brain as a metabolite, which is a substance that deals with the metabolism. The appearance of palmitic acid can be in a dry powder form, liquid, or other solid material. It is often colorless with white crystalline scales. It has a slight distinctive odor and taste but otherwise is odorless. When heated and decayed, it gives off an acrid smoke. The fumes from the smoke can be irritating.
As the first fatty acid to be produced during initial fatty acid synthesis, palmitic acid is a primary part of an animal’s body. Additionally, in humans, palmitic acid has been seen to make up 21% to 30% of human depository fat.
It can be found in blood, cerebrospinal fluid (spinal tap fluid), feces, saliva, sweat, and urine, and also in tissues, including adipose tissue a.k.a. body fat, the bladder, skin, certain cells called fibroblasts, kidney, placenta, platelet, prostate, and skeletal muscle.
Palmitic acid is also known as hexadecanoic acid.
Palmitic Acid Uses
Palmitic acid has several uses. For example, it can be used to test the hardness in water and is a part of the intravenous ultrasonic contrast agent Levovist, which is used during ultrasounds to detect certain diseases.
Palmitic acid can promote smooth skin, so it’s found in many soaps. Additionally, the popular ingredient beeswax, often found in personal care items, also houses palmitic acid. Cosmetic-wise, palmitic acid can be found in makeup used to hide imperfections such as pimples and blackheads.
Another common use for palmitic acid is in cleaning products, typically surface-active agents, such as detergent. It is also used when making metallic palmitates, food-grade additives, and lube oils.
Harmful Effects of Palmitic Acid
Besides an association with breast cancer, palmitic acid has been found to cause other harmful effects, including:
- Genetic disorders: Palmitic acid has been linked to cholesteryl ester storage disease, ethylmalonic encephalopathy, and glycerol kinase deficiency. These disorders are called inborn errors of metabolism. Cholesteryl ester storage disease is a disease affecting the liver, ethylmalonic encephalopathy is a disease primarily of the nervous system, and glycerol kinase deficiency is a disease that causes excessive enzyme defects.
- Nontypified gene mutations: A nontypified gene mutation, also known as organic acidemia, can occur in those who consume palmitic oil. This mutation causes mevalonic aciduria, which is a more severe form of mevalonate kinase deficiency, a genetic autoinflammatory disorder.
- Circulatory system disorders: Circulatory system disorders have also been associated with palmitic oil. These disorders include blood and lymphatic system disorder, or hypercholesterolemia.
- Nervous system disorders: Nervous system disorders, primarily of the central nervous system, have been linked to palmitic oils. This includes the psychiatric disorder of schizophrenia.
- Digestive system disorders: Palmitic oil can also cause digestive issues, primarily in the upper gastrointestinal tract. This issue is known as eosinophilic esophagitis.
A study released in the journal Nature notes that palmitic acid feeds tumors, causing them to expand and become more aggressive. Tumors that have been exposed to palmitic acid are left with memory markers. Memory markers allow tumors to hold onto a significant amount of metastatic or spreading capacity. The effects palmitic acid has on tumors can last for several months. Due to this study, it can be determined that a palmitic acid–favoring diet may speed up the progression of cancer.
In addition, saturated fatty acids, including palmitic acids, have been shown to promote pro-inflammatory responses. This has been observed in human immune cells. While researchers have witnessed their pro-inflammatory powers, how it promotes pro-inflammatory responses is unknown.
A few other disorders and diseases have been linked to palmitic acid, including chemical and drug-induced liver injury, fatty liver, insulin resistance, non-alcoholic fatty liver disease, and cognition disorders.
There have been multiple studies done on the effects of palmitic acid in rats. One study found that rats fed 4.6 grams of palmitic acid a day for six weeks ended up with hyperlipidemia, a condition in which the blood produces too much fat. Another study found that another group of rats developed atherosclerotic abrasions, and hardening of the arteries, when given 6% palmitic acid in their diets over the course of 16 weeks.
Despite these studies and claims, the U.S. Food and Drug Administration (FDA) has said that palmitic acid is a generally recognized as safe (GRAS) substance. Due to this, palmitic acid is often considered an OK additive in food and the making of certain foods.