How much do you know about castor oil? Also, if you’re looking for the best castor oil for skin, hair, eyebrow regrowth or fuller lashes, how will you know which is best?
When I first started to do research about castor oil, there seemed to be very little clinical evidence. However, I could find plenty of anecdotal evidence. People were raving about the benefits and the fantastic results they’d had using castor oil. There were plenty of before and after photos to support the claims.
I realized that different people need different types of evidence to help them decide what to buy. Some shoppers want all the proven, researched facts and will pay a premium for natural and environmentally friendly products. Others might not even know that there’s a debate over certain ingredients. They just want a product that works! Here’s a great article to help you decide what type of shopper you are.
Table of Contents
- What Is Castor Oil?
- Reasons Why Castor Oil Is Good for Your Hair
- Does Castor Oil Promote Hair Growth and Prevent Hair Loss?
- Reasons Why Castor Oil Is Good for Your Skin
- What to Look for if You Want the Best Castor Oil
- Best Castor Oil Product Reviews
So, this article is mix of research and opinions based on what many people are saying about castor oil. I’ll talk a bit about products I have been reviewing and try to give you some guidelines about how to understand the labels so that you can choose the product that is best for you.
What Is Castor Oil?
Here are some interesting facts:
- Castor oil is produced by pressing the seeds of the castor oil plant (Ricinus communis L.).
- Most of the plants are grown in India. Although the USA is the main market for castor oil, there are difficulties with growing it in the USA, not least of which is that the plant contains ricin, which is very toxic to humans. If handled improperly, workers are negatively affected. (The good news is that the oil does not contain any of this poison.)
- Castor oil is a unique vegetable oil because about 90% of its fatty acid content is ricinoleic acid. It is different from all other seed oils, because it is both unsaturated and hydroxylated (I suppose that means something to a chemist!). Castor oil has the unique ability to mix with water and dissolve in alcohol, which is very unusual for an oil. This has something to do with something to do with its polarity. It also has the ability to convert other chemical compounds into new derivatives.
- It is widely used for waxes, greases, paints, coatings, lubricants, brake fluids, polymers, fuel and biodiesel. Most of us have heard about its laxative properties, but it is more widely used in medicine as a drug delivery vehicle. It is also an important ingredient in the cosmetic industry for soaps, cleansers, moisturizers, lipsticks and a host of other products.
Reasons Why Castor Oil Is Good for Your Hair
- Castor oil is said to have anti-inflammatory, antimicrobial and antioxidant properties. This helps with scalp health, and a healthy scalp is one of the first steps to healthy hair.
- The polarity of the oil helps it provide a good "seal" around the hair shaft, preventing loss of moisture. However, this is not an impermeable seal, like you get with a mineral oil. Some of the oil is absorbed into the hair shaft, giving it additional strength. Castor oil is also particularly beneficial during very dry weather.
- The polarity (ie, the ability to mix with water) also has the benefit of making the the oil is easy to rinse off your hair, without the need for shampooing. This is particularly helpful for Afro and textured hair. It means that you can re-wet your hair and re-apply the oil often. There is no buildup on the scalp or hair shaft which can lead to scalp irritation and heaviness in the hair.
- A useful tip is to mix castor oil and coconut oil as a mask on your hair for the night before you shampoo. It prevents "hygral fatigue" (repeated swelling and drying of hair), and the coconut oil reduces protein loss in hair.
Does Castor Oil Promote Hair Growth and Prevent Hair Loss?
Just about every blog you read on castor oil says that it promotes hair growth. This includes growth of eyebrows and eyelashes. There are many videos and photographs supporting these claims. Unfortunately, there are not many clinical studies to support this.
However, here are some documented studies on the subject:
- Massaging your scalp with oil stimulates blood flow, and this has been shown to prevent hair loss and early balding.
- Stimulating hair growth takes time and regular treatment. A study from Japan showed that it took 24 weeks before scalp massages began to show any effect. Growing more hair took anywhere from 2 to 10 years, but when the follicles have shrunk, this growing phase can be just a few months. Scientists link this shrinking of the follicle with high levels of a molecule called prostaglandin D2 (PGD2). Researchers is China found that ricinoleic acid was effective for inhibiting PGD2, and should be further investigated as a possible solution for hair loss. They also found that ricinoleic acid had excellent skin permeability and very little propensity for causing skin reactions. Castor oil is very high in ricinoleic acid, so we expect it to deliver the same results. It is unlikely to reverse hair loss, but it may help prevent further hair loss.
- Another reason for hair loss is oxidative stress, which can be prevented by antioxidants, and especially Vitamin E. Most of the blogs I read said that castor oil is rich in Vitamin E, but I was not able to verify this definitively. If anyone knows the breakdown of all the vitamins and minerals in castor oil, please let me know!
- Castor oil is a humectant, so it attracts water vapor towards the skin and hair. Better moisturized hair looks fuller and glossier. This might lead some people to believe that their hair is growing or getting thicker.
- Androgenetic alopecia (AGA) or male pattern baldness is quite a complicated subject. One of the things that happens is that hair follicles become abnormally small, causing the new hairs that grow from them to be very thin and weak. The normal growing phase for hair can be 2 to 10 years, but it is reduced to a few months with AGA. Some scientists have linked an overproduction of a molecule called Prostaglandin D2 (PGD2) with hair loss. A study in China found that ricinoleic acid seemed to be an effective natural treatment for stopping overproduction of PGD2 and that it was safe to use and unlikely to cause adverse skin reactions. Castor oil is the source of ricinoleic acid, so it makes logical sense to assume that it will have the same effect.
Reasons Why Castor Oil Is Good for Your Skin
Castor oil is the most-used oil in cosmetics, and especially in lipsticks. This is for several reasons:
- It is easily absorbed into the skin and acts as an emollient or softening agent.
- Castor oil can easily carry other nutrients or cosmetic ingredients into the skin.
- The ricinoleic acid acts as an astringent and so it constricts and tightens body tissues. This makes it a great choice for those with very oily skin.
- It is non-comedogenic and will not block the pores. This is mainly because of the low levels of fatty acids such as linoleic and oleic acids.
- It is the most common used base for make-up removers and cleansers for OCM (the oil cleansing method) and is said to restore your skin’s natural oil balance.
What to Look for if You Want the Best Castor Oil
1. Color and Appearance
The most common type of castor oil is the color of pale straw, or somewhat golden. It should be quite thick with a viscosity similar to honey. If it is dark or is cloudy, it is best to discard it. However, there is a "Jamaican Black Castor Oil" which is produced by roasting the castor beans for an extended period. You can read about using this Black Oil for your hair here.
2. Cold Pressed
All extraction of castor oil uses some level of heat. The beans are cooked at the start of the process. High temperatures are used for industrial purposes because up to 80% of the oil can be extracted with heat, while only 45% is extracted with cold pressing. Using temperatures below 50 degrees helps retain the natural properties of the oil, including its vitamin and mineral content.
Castor oil has quite a strong odor, which some people don’t like. If it has no odor, that means that it has gone through several refining steps, including bleaching and deodorization. This usually involves high heat and chemical solvents. Highly refined oils are fine for industrial use, but probably not for your skin and hair.
Technically, there are two grades of castor oil:
- "Pale pressed" or AA Standard from the first pressing of the seed. This is what many people refer to as "virgin". It is lighter in color and is less acidic than industrial grades. It may, however, be diluted and quite thin. It is also important to make sure that your oil is cold-pressed if you want top quality or food grade oil.
- Industrial or "#1 Imported" is when the first pressing is combined back with the next batch of seeds. This process is repeated several times. The seed bulk is finally compressed into "castor cake", crushed again and is often treated with solvents to get the last of the oil out.
5. The Label
A label should give you all the above information. If it doesn’t you can usually assume the worst.
It should be noted that there are ongoing attempts to genetically modify castor oil plants to remove the dangerous ricin toxin. It is unclear whether this will have any impact on the other natural properties of the plant.
Best Castor Oil Product Reviews
I did some research to find several high-quality oils to recommend to you, based on the criteria above:
- Color and appearance
- Cold pressed
- Label gives useful information
I selected products that were advertised for both hair and skin use and that had large numbers of positive reviews. Then I evaluated their labels to see whether they gave sufficient information to potential shoppers. I converted all the prices to cost per 100ml so they could be fairly compared. After that, I looked at any additional benefits claimed for each brand. The results were quite surprising.
Here are the products I looked at. I’ve presented them in the order that I ranked them.
In my review, I made every attempt find out whether there was sufficient information provided to allow for an honest assessment of the quality of the oils. I was surprised by how little was given on some labels, and how difficult it was to find some of the information, even when I went to the company websites. I was also surprised at the huge range of prices for these products – from about $2 per 100ml to about $100 per 100ml!
Here is a summary of how the different brands met the criteria for the best castor oils
Color and appearance
The oil seems to be quite thin compared to others and there are some reports that it is odorless
Why is there such a long shelf life?
100% pure – no additives
100% pure – zero additives, zero fillers
Price per 100ml
(±$47 on sale)
My top pick
My 2nd pick
I recommend that you try some castor oil for hair and skin. Although there are very few clinical studies, anecdotal evidence is strong that castor oil supports hair growth and hair thickness, and this includes eyelashes and eyebrows. It also has good moisturizing properties for skin and nails.
I hope you found this article helpful. Please tell me your stories about how you decide what is the best castor oil.
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