Story at-a-glance

• Compounds derived from coconut oil demonstrate a greater ability to deter bedbugs, ticks and mosquitoes than DEET, including biting stable flies on animals for up to four days with 95 percent effectiveness
• Blood feeding insects are responsible for spreading vector-borne illnesses, such as leishmaniasis, Chagas disease, Japanese encephalitis and malaria
• Possible side effects of DEET include neurological symptoms, weakness, fatigue, nausea and shortness of breath
• You may reduce your risk of being bitten by installing bat homes, as bats voraciously eat mosquitoes, by using a fan on high setting while outdoors, by dressing in long pants and long sleeved shirts or staying indoors from dusk to dawn
• Health benefits of coconut oil are not limited to topical improvements, but also include supporting healthy thyroid function, heart health, brain function and digestion

Hematophagous arthropods are insects or spiders that feed on blood, and transmit human and animal pathogens worldwide. Called vector-borne diseases, the illnesses caused by their bites account for nearly 17 percent of all infectious diseases annually. Nearly 700,000 humans die each year as a result of having acquired an infectious disease from the bite of an insect.1

The Defense Advanced Research Projects Agency (DARPA), an arm of the U.S. Department of Defense, plans to use insects to deliver genetically engineered viruses to plants with an aim to alter the plants genetic traits in the field.2 While the initial intent may have been to genetically control agriculture, it is not difficult to see how it may be easily weaponized.3

Although scientists recognize a reducing number and variety of insects worldwide, and the ecological chaos it would create in the environment, mosquitoes do not appear to be at immediate risk. Repellents have been a primary tool for reducing the bites of insects on humans and animals, with N,N-Diethyl-meta-toluamide (DEET) currently considered the gold standard in insect repellent.

However, with documented health risks, particularly for infants and pregnant women, it is a poor choice. In a recent study by the U.S. Department of Agriculture (USDA), researchers found compounds derived from coconut oil are better than DEET at repelling these insects and protecting your health.4

Compounds Derived From Coconut Oil Repel Insects Better Than DEET

Vector-borne illnesses are preventable using repellents to prevent transmission. For more than 60 years, DEET has been available commercially for this purpose. However, with rising health concerns over insecticides, there is an increased interest in developing effective, long-lasting and plant-based repellents.

A team of researchers led by entomologist Jerry Zhu with the USDA’s Agricultural Research Service Agroecosystem Management Research Unit, analyzed data using coconut oil compounds against biting insects and bedbugs. Their data revealed the compounds had a strong repellency against mosquitoes and ticks.5

The repellent is not pure coconut oil, but a free fatty acid mixture of lauric acid, capric acid and caprylic acid derived from the coconut oil. Encapsulating these coconut fatty acids into a starch-based formula, researchers used field trial testing to demonstrate it could also protect cattle against biting flies for up to four days.

By comparison, DEET was only 50 percent effective against biting flies, while the coconut oil compound was more than 95 percent effective. The researchers compared the coconut oil compound against DEET on bedbugs and ticks and found DEET lost effectiveness after three days while the coconut oil compound was effective in repelling bedbugs and ticks for nearly two weeks.6

Additionally, researchers tested the coconut oil fatty acids against mosquitoes on human participants, including the species responsible for transmitting the Zika virus, and found more than 90 percent repellency. According to the USDA, these coconut oil-derived compounds offer a longer-lasting protection against blood feeding insects then other known natural repellents.

Picaridin and Lemon Eucalyptus Also Beat DEET for Repelling Insects

In other testing, Consumer Reports recruited volunteers to test out spray-on repellents made of DEET, oil of lemon eucalyptus, picaridin, a chemical called IR3535, and products made with natural plant oils. After the repellents were applied and allowed to sit for 30 minutes, the volunteers reached into a cage containing (disease-free) mosquitoes or ticks.7

Two products emerged on top and were able to keep mosquitoes and ticks away for at least seven hours: products that contained 20 percent picaridin or 30 percent oil of lemon eucalyptus. Picaridin resembles the natural compound piperine, an essential oil in black pepper.

However, picaridin is not a natural compound; it's produced synthetically in the lab. According to the Environmental Working Group (EWG), picaridin does not carry the same neurotoxicity concerns at DEET, although it has not been tested much over the long term. In the EWG’s assessment8 "Picaridin is a good DEET alternative with many of the same advantages and without the same disadvantages."

Dangers of DEET

Not only do mosquitoes carry disease, but their bite creates an inflammatory response that can remain itchy for days. While the number of mosquitoes can be annoying, it is not wise to spray a bunch of chemicals on your skin to solve the problem. In 1946, the U.S. Army patented DEET, which is still widely recognized as an effective mosquito repellent.9

Although some support the use of DEET in small quantities, you will likely use more than small quantities if you spend time outdoors through the summer months. Prolonged exposure may impair cell function in parts of your brain, as demonstrated by death and behavioral changes in rats with frequent or prolonged use.10

When rats were treated with the average human dose equivalent of DEET, they performed far worse than control rats on physical tests requiring muscle strength, control and coordination.11 These results are consistent with reports of symptoms after the military used DEET in the Persian Gulf War. Heavy exposure can trigger:12

Eye and skin irritation

Memory loss

Headaches

Weakness

Fatigue

Muscle and joint pain

Nausea

Tremors

Shortness of breath

Unfortunately, these symptoms can appear months and even years after prolonged use of the chemical. While Duke University Medical Center pharmacologist Mohamed Abou-Donai, Ph.D., believes short-term exposure may not be harmful, he warns against ever using a product with more than 30 percent concentration.13 

Unfortunately, exposure to DEET over the summer months may be frequent and long-term, and researchers have found the combined exposure with DEET and other chemicals is actually more dangerous than using DEET alone.14 Skin care products, deodorants, soaps and sunscreens, when mixed with DEET, increase toxic potential of the chemical.

Children are also more susceptible than adults to changes in their brain triggered by chemicals in the environment, as their skin more readily absorbs them and their neurological system is still developing.

In a study of more than 140 National Park Services employees, the U.S. Centers for Disease Control and Prevention (CDC) found neurobehavioral analysis demonstrated correlations between DEET exposure and depression, anxiety, insomnia, muscle cramps and urinary hesitation. Skin rashes and blisters were also reported.15

Numbers of Vector-Borne Illnesses Rising

The annual number of people who get sick from vector-borne diseases has more than tripled since 2004.16,17 The World Health Organization (WHO)18 concluded climate change is likely a contributor, as warmer global temperatures have expanded the habitats of mosquitoes, ticks and other disease-spreading bugs.

Mosquitoes and ticks are responsible for nearly 77 percent of all vector-borne diseases. Dr. Lyle Petersen, director of the Division of Vector-Borne Diseases in the National Center for Emerging and Zoonotic Infectious Diseases at the CDC said,19 “We desperately need to find new ways to deal with ticks and mosquitoes. We need better ways of controlling them and better diagnostic tools.”

According to the WHO,20 deaths attributed to vector-borne diseases include conditions such as malaria, schistosomiasis, leishmaniasis, Chagas disease and Japanese encephalitis. The highest burden is experienced in tropical and subtropical areas.

Distribution of these diseases is determined by complex demographic, environmental and social factors. Greater global travel and trade, as well as environmental challenges and unplanned urbanization have impacted pathogenic transmission and increased transmission seasons, triggering outbreaks in countries where they were previously unknown.21

Protect Yourself Against Vector-Borne Disease

Your best options are to reduce mosquito populations in your area through natural means and to use safe repellents. Consumer Reports tested three nonchemical options: a citronella candle, a portable diffuser with essential oils and an oscillating fan set at the highest speed.

While neither the candle nor the diffuser produce positive results, the fan cut mosquito landings by 45 to 65 percent for those sitting near the fan. You may also avoid insect bites by staying inside between dusk and dawn when they are most active.

Mosquito populations are higher in treed areas and near standing water. The American Mosquito Control Association (AMAC) recommends the “3Ds” of protection to prevent mosquito breeding on your property:22 

• Drain — Mosquitoes require water to breed, so carefully drain any and all sources of standing water around your house and yard, including pet bowls, gutters, garbage and recycling bins, spare tires and bird baths.
• Dress — Wear light-colored, loose fitting clothing, such as long sleeved shirts and long pants, hats and socks.
• Defend — While the AMCA recommends using commercial repellents, I highly recommend avoiding most chemical repellents for the reasons already discussed; instead, try some of the natural alternatives when necessary.

Engage the mosquitoes’ enemy by providing a habitat for bats in your yard. These are voracious insect eaters who will help keep your mosquito population at bay. For more on buying a bat house or constructing one yourself, visit Bat Conservation International.23 Planting marigolds around your yard also helps reduce your mosquito population as mosquitoes dislike the fragrance.

Health Benefits of Coconut Oil

While the mosquito repellent used in the featured study used coconut oil-derived compounds, there are additional health benefits to using the natural oil. Nearly 90 percent of the fat in coconut oil is healthy saturated fat, unlike the hydrogenated oils and trans fats that trigger inflammation and damage to your arterial system.

Half the fat in coconut oil is lauric acid, a medium chain fatty acid with antibacterial, antiviral and antiprotozoal properties. Your body converts this to monolaurin, which can actually destroy lipid-coated viruses. You may also enjoy a number of other benefits when you incorporate coconut oil in your nutritional intake, including:

Support healthy thyroid function — Unlike soy oil and other vegetable oils,24 coconut oil does not interfere with thyroid function. It has anti-inflammatory properties helping to reduce inflammation that may lead to hypothyroidism and hyperthyroidism.25

Promote heart health — Animal and human studies have found heart disease risk factors such as total, LDL and HDL cholesterol levels contributing to poor cholesterol ratios are improved by taking coconut oil. In particular, the saturated fats in coconut oil may increase "good" HDL cholesterol, while also helping convert "bad" LDL cholesterol into a less harmful form.26

Promote healthy brain function — Research data determined ketones may work as an alternative energy source for malfunctioning brain cells, which has been found to reduce symptoms in patients with Alzheimer's disease.27

Boost immune function — Lauric acid, antimicrobial lipids, capric acid and caprylic acid coconut oil contains are known for their antifungal, antibacterial and antiviral properties.28 Regularly using it may help prevent colds/flu, and alleviate illnesses like hepatitis C, herpes and the Epstein-Barr virus.29

Boost energy — Medium-chain fatty acids (MCTs) in coconut oil are immediately digested and converted into energy by your liver.

Aid weight loss — Coconut oil provides an excellent fuel for your body and stimulates your metabolism to help you shed excess body fat, especially when combined with a cyclical ketogenic nutrition plan.

Aid digestion — Coconut oil is easy on your digestive system and will not produce an insulin spike in your bloodstream. The MCTs can also be absorbed easily in your digestive tract, compared to longer chain fatty acids found in polyunsaturated vegetable oils.

Control Crohn's disease — Research demonstrates healthy plant-derived fats, such as coconut oil, can bring about positive changes in your gut bacteria, decreasing the symptoms of Crohn's disease, an often debilitating condition.

Maintain healthy, youthful looking skin — Application of coconut oil topically benefits your skin, reducing the appearance of wrinkles and fine lines as the oil keeps your connective tissues strong and supple. Limited evidence also suggests it may boost collagen production,30 although the mechanism of action is unknown.

Control Candida — A study published in mSphere found mice given coconut oil had a tenfold drop in the colonization of Candida albicans yeast in their gut, compared to mice given soybean oil or beef tallow.31

Promote oral health — One study found massaging coconut oil on your gums for 10 minutes a day for three weeks significantly reduces plaque and decay-causing Streptococcus mutans.32 In another study, oil pulling, a traditional practice of swishing oil in the mouth, decreased plaque within the first seven days of practice.33