Shea butter is a yellowish fat obtained from the nut of the African shea tree. Well-known for its beneficial effects on the skin and hair, shea butter can help with skin irritation, eczema, aging, and more. Still, the clinical evidence remains limited. Read on to learn the benefits, uses, and side effects of shea butter.
What is Shea Butter?
Shea butter in its natural form is obtained from the nut of the shea tree (Vitellaria paradoxa), mainly located in sub-Saharan Africa [1].
It consists of a variety of fatty acids including oleic acid, stearic acid, linoleic acid, and palmitic acid, which vary in proportion, depending on its tree of origin [2].
Natural shea butter contains vitamins A and E, which are the main factors responsible for the moisturizing and protective effects shea butter has on the skin [3].
In modern times, shea butter has a vast variety of uses, especially in the cosmetic industry. Due to its anti-inflammatory and antioxidant properties, shea butter is usually found in products like skin moisturizer creams and hair conditioners [4].
Shea butter is also used to make skin-friendly pharmaceutics used for conditions like acne, eczema, and arthritis [5, 6, 7, 8].
There are several types of shea butter, depending on the quality of the product. According to the American Shea Butter Institute, there are 4 types of shea butter: Classes A, B, C, and F, listed from the highest quality to the lowest [9].
Snapshot
Proponents:
- Nurtures the skin
- Helps with eczema
- Relieves skin irritation
- May relieve nasal congestion
- May reduce joint pain
Skeptics:
- Clinical evidence is limited
- May be contaminated with chemicals
- Expensive
- Has an unpleasant smell
Components
Shea butter mostly consists of fats, vitamins, and phenolic compounds [3].
Fats
- Oleic acid is a fatty acid mostly present in vegetable oils. It is commonly used in skin products, like soaps and creams, as a moisturizer [10].
- Stearic acid is a fatty acid present in animal and vegetable oils. It is used as a lubricant in a variety of cosmetics [11].
- Linoleic acid is an anti-inflammatory fat that prevents acne formation when applied to the skin [12].
- Palmitic acid is a fatty acid with lubricant properties, commonly used in greases [13].
- Arachidic acid is the fatty acid with the lowest presence in shea butter. It is also used in beauty products as a moisturizer [3].
Phenolic Compounds
Eight phenolic compounds from the catechin group were identified in shea butter. The most abundant phenolic compound present in shea butter is gallic acid. Catechin compounds are known for their antioxidant properties [3, 14].
Vitamins
- Among other functions, vitamin A has the ability to correct skin defects like wrinkles and acne. It acts as a skin regulator; it can turn immature skin cells into mature ones and has the ability to correct skin defects [15].
- Vitamin E is well-known for being one of the most important skin protectors, reversing natural skin aging. It can also be helpful against skin burns and acts as an anti-inflammatory [16].
Triterpene Alcohol Compounds
Shea butter contains a considerable amount of triterpene alcohol compounds, which are in essence, another type of fat. The most common triterpenes found in shea butter are alpha-amyrin, beta-amyrin, lupeol, and butyrospermol. These triterpenes have anti-inflammatory and anti-tumor properties [3, 17].
Product Quality
There are 2 types of shea butter, raw and refined. Compared to refined shea butter, raw shea butter is more natural and doesn’t contain chemical contaminants [18].
Among other factors, the climate in which the shea tree is located plays a significant role in the quality of the final product. For example, shea trees that are located in cold areas have lower levels of vitamin E compared to trees located in hot and dry areas [4].
Mechanism of Action
In order to have an effective impact on human skin, shea butter must reach and penetrate several layers of skin tissue. To achieve this goal, several fats present in shea butter like oleic, stearic, and palmitic acids interact with fats (lipids) present on the skin [11].
Anti-Inflammatory Properties
Normally, skin inflammation is caused by environmental factors (like UV radiation, burns, chemicals, toxins, etc.) that eventually lead to premature skin aging. Shea butter components like triterpenes reduce the production of inflammatory molecules (e.g., prostaglandins, myeloperoxidase, and cytokines), thereby slowing down skin aging [19, 5, 20].
One of the main components of shea butter is lupeol, a triterpene. Lupeol regulates certain genes that are related to the skin’s physical appearance and inflammation [21].
Animal and cell-based studies have shown that several shea butter components, especially lupeol, reduce skin inflammation [5, 22].
One study in rats found that lupeol, a component of shea butter, decreased paw swelling (by 39%) by reducing inflammation [23].
A cell-based study showed that shea butter reduced levels of tumor-inducing and pro-inflammatory enzymes (iNOS and COX-2) [22].
Health Benefits of Shea Butter
Possibly Effective:
1) Atopic Dermatitis (Eczema)
One 4-week study in 34 patients with eczema found that a cream with shea butter extract reduced skin itching and improved quality of life in 74% of subjects [6].
Similarly, in another pilot study of 25 subjects with eczema, natural remedies like moisturizers with shea butter oil reduced itching (by 79%) and increased skin hydration (by 44%) [24].
In 29 children, a cream with shea butter and argan oil was equally effective as a corticosteroid cream in reducing the symptoms of atopic dermatitis [25].
Insufficient Evidence:
No valid clinical evidence supports the use of shea butter for any of the conditions in this section. Below is a summary of up-to-date animal studies, cell-based research, or low-quality clinical trials which should spark further investigation. However, you shouldn’t interpret them as supportive of any health benefit.
2) Nasal Congestion
Nasal congestion is a common symptom found in several diseases like the common cold or rhinitis, in which nasal passages are blocked [26].
In one study of 33 people with rhinitis (nasal inflammation), topical shea butter was equally effective in relieving nasal congestion as xylometazoline, a decongestant drug [27].
3) Arthritis
In one study of 33 patients with knee osteoarthritis, shea butter extract taken orally in pill form (SheaFlex75) relieved knee pain and improved muscle control [8].
4) Skin Irritation/Injury
Fats like oleic acid and stearic acid present in shea butter are responsible for the butter’s moisturizing effects. For this reason, most of the fats present in shea butter are used as main components in common beauty products [10, 11].
A population-based (case-control) study in Africa observed that shea butter had a protective effect on the skin when applied topically to the cord stump of newborn babies and its surrounding areas [28].
5) Skin Aging
Skin aging is a natural process in which the skin oxidizes, leading to tissue deterioration. Everyone experiences skin aging sooner or later, but this process can be accelerated by environmental factors like UV radiation, stress, diet, etc. [29].
Shea butter is rich in antioxidant components like phenolic compounds and vitamins A and E. These components prevent skin oxidation and aging, but studies are yet to investigate the effects of shea butter on skin aging [3].
Animal and Cellular Research (Lacking Evidence)
No clinical evidence supports the use of shea butter for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based studies; they should guide further investigational efforts but should not be interpreted as supportive of any health benefit.
Skin Scarring
A scar is the natural healing response of the body; when the skin is wounded, the original skin will be replaced by scar tissue [30].
A keloid is a type of scar that is significantly larger than a normal scar. African tribes have used natural shea butter as a remedy to treat keloids [31].
In a cell-based study, shea butter reduced the growth and production of keloid connective tissue cells (fibroblasts) [31].
Wound Healing
Shea butter is abundant in triterpenes, compounds that enhance tissue repair by accelerating wound closure and reducing the production of ROS in the wound microenvironment [32].
Other
Although there is a popular opinion supporting the use of shea butter for these conditions, there is no scientific evidence backing its use for:
- Stretch marks: Because of its anti-inflammatory and antioxidant properties, shea butter is a common ingredient in products that are used to treat stretch marks. A review of topical stretch mark therapies found that women who used a product containing shea butter to treat stretch marks had more skin elasticity and reduced stretch marks. However, the quoted studies haven’t been published [33].
- Sunburns: Shea butter is reported to treat sunburns. However, there are no studies to confirm its effectiveness in doing so. Vitamin E, which is found in shea butter, has been used as a preventative treatment against sunburns [34, 35].
Shea Butter Negatives & Limitations
Limitations and Caveats
Overall, there is a great deal of information on the internet about the potential benefits of shea butter. Nevertheless, there are several aspects that need to be improved in order to avoid misinterpretation of the product.
- Lack of scientific information about actual shea butter benefits. Some of the benefits listed above involved studies about shea butter’s components, but not about shea butter itself [34, 36].
- Lack of safety trials. There are very few studies on the side effects of natural shea butter, giving the misleading impression to the user that the butter can be safely used by anyone. This is especially important for oral shea butter consumption [37, 38, 39].
- Availability of studies made by companies. Several cosmetic companies carry out their own studies to provide better products. The problem is that most of the time these studies are not shown to the public, which gives the study less validation [33].
- Lack of clinical evidence. Several health benefits listed above were observed in animal and cell studies only. The problem with these types of studies is that they can misguide the population about the actual effect of shea butter on the human body [5, 22].
1) Usually Expensive
One of the main problems of shea butter is its price. Shea butter is usually obtained in small quantities and has a very high demand; thus, the price of the product increases in a considerable way [40].
2) Has a Distinctive Smell
One of the main cons of shea butter is its smell. The odor of shea butter is known to be kind of strange and distinctive when applied to the skin. In fact, one of the main objectives of shea butter’s industrialization is to get rid of that peculiar smell [41].
Shea Butter Side Effects & Precautions
Shea butter is considered safe by the FDA for oral consumption in the amounts naturally found in foods. Topical application is also safe and well-tolerated [42, 3].
As previously mentioned, there are several types of shea butter, depending on the quality of the product: Classes A, B, C, and F, listed from the highest quality to the lowest [9].
Refined Shea Butter
Class A raw butter doesn’t have any side effects. On the other hand, refined shea butter is processed with many chemicals, some of which may be harmful to health, like n-hexane [18, 43].
N-hexane is a substance used for extracting shea butter from its kernel. When ingested in small proportions, n-hexane can cause drowsiness, fatigue, loss of appetite, muscle weakness, and headaches [18, 44].
Natural Sources and Forms of Supplementation
Although shea butter may be edible in its natural form, it is normally applied directly on the skin, like a cream [45].
Generally, shea butter is an ingredient in beauty products like soaps, cosmetics, creams, cleansers, and ointments [6, 46, 47].
Because of its high nutritional value, shea butter can also be used in foods such as baking fat, margarine, and chocolates [46].
Shea Butter and Coconut Oil
Shea butter is a fat-rich substance that contains oleic acid. Oleic acid is normally used as a long-lasting moisturizer [10].
Coconut oil, a vegetable oil extracted from coconuts, is rich in saturated fats. One of the main components of coconut oil is lauric acid, which has potent antimicrobial properties. The mixture of shea butter and coconut oil combines the properties of both and creates a product that moisturizes the skin and fights bacterial infections [48, 49, 50].
User Reviews and Experiences
The opinions expressed in this section are solely from the users who may or may not have a medical background. SelfDecode does not endorse any specific product, service, or treatment. Do not consider user experiences as medical advice. Never delay or disregard seeking professional medical advice because of something you have read on SelfDecode.
Plenty of users enjoy skincare products with shea butter and report their beneficial effects on irritated and dry skin, including skin conditions such as eczema and psoriasis.
An unpleasant smell is the most common complaint. Some users reported skin itching due to a potential allergy.
