Positive and Negative Effects of Perilla Oil
Perilla oil is one of the richest sources of plant-based omega-3 fatty acids, in the form of alpha-linolenic acid. Omega-3 fatty acids are considered essential because they can’t be made in the body and must be consumed in the diet. Perilla oil has several potential health benefits, mainly, reducing cholesterol and potentially preventing heart disease. However, other studies have found a negative effect of perilla oil consumption.
What is Perilla Oil?
Perilla oil is obtained from the seeds of a species of mint plants called Perilla frutescens. The perilla plant is native to Southeast Asia and India and has been used medicinally in China for thousands of years [R].
Perilla oil is popular because it is a plant source of essential omega-3 polyunsaturated fatty acids. Fatty acids are considered essential if they cannot be produced by the body and must be obtained via diet. The main omega-3 fatty acid in perilla oil is alpha-linolenic acid, which comprises 54 – 69% of the oil [R, R].
Like many plants, perilla contains a wide variety of beneficial phytochemicals and compounds. The main compounds are [R]:
- Essential oils
- Fatty acids
- Flavonoids and triterpenes
- Phenolic compounds/polyphenols
Perilla seeds contain many essential oils, such as p-Cymene, beta-caryophyllene, and alpha-farnesene. The leaves and stems contain essential oils, as well, like limonene and eucalyptol, among others [R].
- Alpha-linolenic acid (omega-3 essential polyunsaturated fatty acid)
- Lauric acid (saturated fatty acid)
- Linoleic acid (omega-6 polyunsaturated essential fatty acid)
- Oleic acid (omega-9 monounsaturated fatty acid)
- Palmitic acid (saturated fatty acid)
- Stearic acid (saturated fatty acid)
Perilla oil is a good source of omega-3 polyunsaturated fatty acids since 54-64% of it is alpha-linolenic acid. alpha-linolenic acid is a plant-derived omega-3 fatty acid, similar to those found in fish oil, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) [R, R].
Health Benefits of Perilla Oil
1) Perilla Oil May Reduce Cholesterol Levels
In a study with 86 people with high cholesterol, those supplemented with perilla oil had lower levels of total cholesterol, LDL, oxidized LDL, apolipoprotein B activity, and lipoprotein-associated phospholipase A2 (a marker for heart disease) activity [R].
In rabbits, perilla oil generated a similar reduction in total cholesterol, LDL, and triglyceride levels as Lovastatin treatment (a cholesterol medication), and both treatments reduced accumulation of fat in the liver and kidneys [R].
2) Perilla Oil May Prevent Heart Disease
A clinical trial with 605 people who had a heart attack compared the alpha-linolenic acid-rich Mediterranean diet with a typical diet recommended to heart attack patients. People on the Mediterranean diet had fewer second heart attacks and heart disease-related deaths [R].
Similarly, a study of over 43,000 men found that alpha-linolenic acid was correlated with a lower risk of developing heart disease [R].
However, a meta-analysis of 89 studies found no relationship between omega-3 fatty acid consumption and heart disease. The source of the omega-3 fatty acids did not matter [R].
3) Perilla Oil May Treat Asthma
In a clinical trial of 14 people, those who consumed perilla oil had improved lung function. They also had decreased levels of the inflammatory compounds, leukotriene B4 and C4 [R].
4) Perilla Oil Can Potentially Fight Cancer
A study of 121 women with breast cancer found that, aside from tumor size, low levels of alpha-linolenic acid in breast tissue was the only predictive indicator of metastasis, the spreading of cancer to other parts of the body [R].
In a rat study, perilla oil reduced the occurrence of colon, breast, and kidney tumors more than the omega-6-dense soybean and safflower oils. In another rat study, perilla oil was also associated with a reduced risk of colon cancer [R, R].
However some studies have found that alpha-linolenic acid may increase prostate cancer risk, so more studies are needed [R].
In a study of aging mice, the mice fed perilla oil had lower cholesterol and grew fewer tumors. However, they also had shorter lifespans, with an average decrease of nearly 70 days. The authors were not able to explain this apparent contradiction [R].
5) Perilla Oil May Reduce Osteoporosis Symptoms
In a study of elderly adults, high consumption of alpha-linolenic acid was correlated with a reduced risk of hip fracture over the course of 16 years [R].
Animal and Cellular Studies
The following studies were only conducted on animal models and/or cell lines.
6) Perilla Oil May Improve Cognitive Function and Memory
Rats fed perilla oil performed better in a maze test than rats fed corn oil. Those that consumed perilla oil had changes in the protein levels in the brain [R].
Rats fed a diet rich in either perilla oil or fish oil had changes in gene activation in the brain. The genes affected may increase calcium signaling, stimulus responses, and neuron stability [R].
7) Perilla Oil May Help With Weight Loss
In a rat study, animals were fed a diet of perilla oil, safflower oil, olive oil, or beef fat. Rats fed a diet with perilla oil had less fat and lower cholesterol than the other groups [R].
Young guinea pigs that were fed diets with low levels of alpha-linolenic acid had increased weight gain compared to guinea pigs with normal levels of alpha-linolenic acid during development [R].
8) Perilla Oil May Help Clogged Arteries
While not as effective as Lovastatin (a cholesterol medication), perilla oil also reduced arterial plaque coverage by 60% in rabbits [R].
9) Perilla Oil May Boost Liver Health
10) Perilla Oil May Prevent Blood Clots
In rabbits, perilla oil reduced platelet clumping (blood clots). High doses of perilla oil were comparable to aspirin in preventing clotting [R].
11) Perilla Oil May Treat Colitis
In a rat model of Crohn’s disease, a diet with perilla oil reduced the severity of the ulcers and lowered levels of an inflammatory compound, plasma leukotriene B4 [R].
12) Perilla Oil Has Anti-inflammatory Properties
13) Perilla Oil Has Antimicrobial Effects
Perilla oil may be beneficial for fighting bacterial infections. When grown in the presence of perilla oil, antibiotic-resistant Staphylococcus aureus strains secreted fewer toxins. This effect was most pronounced for enterotoxins that harm the gut and cause food poisoning [R].
Potential Downsides to Perilla Oil Consumption
Very high levels of dietary perilla oil may actually contribute to insulin resistance. In a rat study, while a diet with 25% perilla oil decreased triglycerides and total cholesterol, it also reduced insulin sensitivity. More studies are needed to confirm this finding and determine the mechanisms [R].
2) Prostate Cancer
The literature on human studies of prostate cancer risk with alpha-linolenic acid is mixed, with some studies suggesting greater prostate cancer risk with high dietary alpha-linolenic acid while others demonstrate a lower risk. Ultimately, more studies are needed before this can be resolved [R].
There are no known side effects to perilla oil consumption but more studies are needed.
Limitations and Caveats
Most of the studies on perilla oil were conducted only on animal models and/or cell lines. Many more human studies need to be conducted.
Although there are limited data on the interactions between drugs and perilla oil, because of its effect on blood clotting, those taking medications such as blood thinners should consult with their doctors before consuming perilla oil.
Pregnant or Breastfeeding?
Please consult your doctor if you are pregnant or breastfeeding before taking any supplements.
Forms of Supplementation
Perilla oil is available as an oil for cooking or as an essential oil or as capsules.
The main active component of perilla oil, alpha-linolenic acid, is also available as a supplement, in the form of capsules.
There is no standard dosage for perilla oil, as more human studies are needed. The range of dosages is large, from 500-20,000 mg/day.
Perilla Oil vs Fish Oil
Fish oil is another good source of omega-3 fatty acids. However, unlike perilla oil, which is high in alpha-linolenic acid, fish oil contains longer-chain omega-3s, especially EPA and DHA [R].
In certain diseases, perilla oil and fish oil have similar effects. For example, in a study of rats with non-alcoholic fatty liver disease (NAFLD), both perilla oil and fish oil reduced inflammation and liver damage that arose from consumption of a high-fat diet by decreasing harmful gut bacteria such as E. coli [R].
Perilla Oil vs. Other Vegetable Oils
Many vegetable oils are high in polyunsaturated fatty acids, yet they each have a unique distribution of fatty acids. Like perilla oil, flaxseed oil has high levels of alpha-linolenic acid, and both have shown heart-healthy effects of increased EPA and DHA levels [R].
Olive oil, by contrast, mainly consists of the monounsaturated fat oleic acid. Safflower oil and sunflower oil normally have high amounts of the omega-6 fatty acid linoleic acid so varieties with increased oleic acid and decreased linoleic acid have been cultivated [R, R].
One user said besides reducing her arthritis symptoms, perilla oil also got rid of her adult acne.
One user said it was a good vegetarian alternative to fish oil.
Another user said that fish oil causes bruising but perilla oil does not.