Natural Treatments for Cold and Flu

16 min. read

Written by:

The common cold and influenza (flu) are caused by viruses, not bacteria. Therefore, antibiotics are ineffective. And the antiviral drugs aren't any better.

Most of the current development has focused on creating drugs that render the viruses incapable of penetrating healthy cells. But because viruses can mutate into hundreds—perhaps thousands—of forms, creating such drugs is largely ineffective.

In fact, the current drug of choice being prescribed to flu patients is the antiviral drug oseltamivir (Tamiflu). But Tamiflu has become virtually worthless in fighting seasonal flu. According to CDC data, among 1,148 seasonal flu samples tested, 1,143, or 99.6 percent, were resistant to Tamiflu.

Natural Treatment for Colds and Flu

So, if you come down with the common cold or flu, do you have real treatment options? Fortunately, the answer is "yes." These all-natural treatment options are some of the best for treating the common cold, flu, and other seasonal illnesses.

Elderberry Extract

Sambucol comes from the Latin name for elderberry, which is Sambucus nigra. It is an elderberry extract from Israel and is used as a common cold and flu remedy.

Sambucol has been shown effective at inactivating viruses, which is no small feat. Sambucol is a powerful antioxidant that stimulates the immune system by increasing production of disease-fighting lymphocytes. It comes in liquid syrup or lozenge form. The recommended dosages of Sambucol are:

  • Children under 1 year old: 2 tsp. daily
  • Children 1–6 years old: 1 or 2 T. or 2 lozenges daily
  • Children 6–12 years old: 2–3 T. or lozenges daily
  • Children over 12 and adults: 4 T. or lozenges

Take the recommended dosage at the first sign of the flu and the virus should disappear within 24 to 48 hours. Since Sambucol is slightly acidic, it should be taken following meals to avoid stomach upset. Sambucol can be found in health food stores.

Eucalyptus Oil

The eucalyptus tree is an evergreen tree native to Australia. The oil from the leaves has been used in cough drops, cold medicines, mouthwashes, toothpaste, detergents, and liniments for arthritic pain.

Eucalyptus oil can be toxic if taken internally. But because of the potent bactericides it contains, breathing the fumes can knock out infections in the nasal passages, sinuses, bronchial tubes, and lungs, with incredible speed. This is especially important in the fight against H1N1 because this flu infects both the upper respiratory tract and the lungs, making pneumonia a grave concern for the small subset of patients who have serious complications from this virus.

To use, put 8–10 drops of eucalyptus oil on a handkerchief and keep it close enough to your nose so that you can inhale the fumes. Or, 10–15 drops can be added to a vaporizer or to some boiling water on the stove to help ease congestion. Eucalyptus oil can be purchased in health food stores or herb shops.


Active hexose correlated compound, or AHCC, is a mushroom extract and immune system stimulator. AHCC supports the immune system by aiding your body's own natural killer (NK) cells, which provide the first line of defense for dealing with any form of invasion to the body.

AHCC increases the amount of "ammunition" NK cells have to attack pathogen-infected cells. In addition, oral ingestion of AHCC increases levels of interferon, a potent compound produced by the body that has been shown to not only increase NK activity by 300 percent or more, but also increase the activity of other key immune cells like T-cells and B-cells, as well as inhibit the replication of viruses.

AHCC is nontoxic and poses no danger or ill effect from long-term use.

For maximum effectiveness during the acute phase of the flu, take 3 grams per day. Once the NK cell activity increases and you begin to feel better, you can drop back to a dose of 1 gram per day. I suggest dividing the daily dosage, whether you're taking 3 grams or 1 gram, and take half of it at breakfast and the other half at dinnertime. The AHCC used in much of the research already conducted is sold as ImmPower.

Castor Oil

Castor oil is a triglyceride of fatty acids. Almost 90 percent of its fatty acid content consists of ricinoleic acid, which has been shown to be effective in preventing the growth of numerous species of viruses, bacteria, yeasts, and molds.

The most effective use of castor oil is through topical packs.

Usually applied to the abdomen, castor oil packs improve the function of the thymus gland and other parts of the immune system. It does this by increasing the production of lymphocytes, the disease-fighting cells in your immune system. With more lymphocytes in your blood, your body is better able to remove toxins from your cells. In turn, your body then becomes less acidic, your organ function improves, and you have increased energy.

Your local health food store should have cold-pressed castor oil.

Zinc Lozenges

Zinc (in particular zinc gluconate lozenges) has been shown to shorten the duration of common cold and flu symptoms by an average of three days compared to a placebo.

If you're coming down with something, start taking one 23 mg zinc gluconate lozenge every two waking hours. The only side effect associated with zinc is its bad taste, which can be addressed using citrus-flavored lozenges such as Cold-EEZE. Even so, this routine shouldn't be continued longer than a week because excessive zinc can eventually create a copper deficiency and weaken the immune system.


Though researchers have yet to identify precisely how this homeopathic remedy works, its results are amazing when taken at the first sign of flu. Oscillococcinum is especially good for children.

Packaged in individual doses of little pellets that dissolve under the tongue, it's easy to take, has a pleasant taste, and is gentle, safe, and nontoxic.


Echinacea angustifolia is an herb that has been shown to significantly increase certain immune responses and inhibit viral activity such as the flu. Research indicates that echinacea binds to receptors on the surface of white blood cells, literally turning these immune cells "on."

I recommend using the liquid plant extract. For adults, put 5–10 drops in ¼ cup of water and take 5 times daily.

Vitamin D

Adequate amounts of vitamin D are essential for your innate immune system to function optimally. Typically, vitamin D levels begin to drop during the winter months as our exposure to the sun also decreases. I feel one of the best things you can do to strengthen your immune system this time of year is for you and everyone in your family to supplement with vitamin D. 

At the first sign of flu, up your daily vitamin D dose to 1,000 IU per pound of body weight per day for a week.

Example: 170 lbs X 1,000 IU vitamin D = 170,000 IU daily

Continue this protocol until symptoms improve, and then scale back to your usual maintenance dose (below).

Vitamin C

Loading up on vitamin C beyond your daily maintenance dose provides extra immune support during a bout of the flu. In addition to its own antiviral activity, vitamin C also:

  • Protects white blood cells
  • Boosts levels of virus-fighting interferon and natural killer cells
  • Fortifies the mucous membranes
  • Has its own antiviral activity

At the first sign of illness, take 500–1,000 mg of vitamin C every waking hour. To avoid possible gastrointestinal upset, build up gradually by taking 500 mg every two hours on the first day and moving up to the higher dose on the second day. Take no more than 10,000 mg per day, and ease back to your usual dose as symptoms improve.

Prevention Is the Best Medicine

Of course, the goal should always preventing cold and flu in the first place. You can make yourself less prone to infection with the following habits.

Back to Basics

These simple but basic prevention methods are well known, but they do bear repeating:

  • Wash your hands regularly with soap and running water for 20 seconds.
  • Cough into a tissue (and throw it away), or into your elbow.
  • Keep your hands away from your eyes, nose, and mouth.

In addition to these steps, there's something much more powerful you can do for preventing cold and flu—and that's to bolster your immune system:

Stay Hydrated

Keeping your body hydrated is such a basic step for good health that it's often overlooked. Experts agree that you should get a minimum of eight 8-ounce glasses of pure, clean water each day. But if your immune system is challenged, then you should increase this amount to 12 8-ounce glasses of water daily.

The real trick here might not be training yourself to consume this amount of water each day, but finding a source of water that's truly clean and pure. My first choice for safe drinking is distilled water because distillation safely removes all contaminants, leaving behind pure H20 just as Mother Nature intended.

Make Smart Food Choices

Plant foods are low in fat, moderate in protein, and contain an abundance of vitamins, minerals, essential fatty acids, and protective phytochemicals—exactly the type of fuel your immune system thrives on. Simply eating more healthy fruits, vegetables, seeds, and grains can dramatically change your body's nutrient levels and increase its antioxidant activity. Plants are also nature's only source of dietary fiber. Insoluble fiber promotes bowel regularity, which is key for the efficient removal of toxins from your body.

Lean protein is important as well. The protein in your immune-boosting diet should come from lean sources such as poultry, fish, egg whites, nonfat yogurt, beans, and grains. Try to eat cold-water fish, such as salmon, mackerel, herring, and cod, several times a week and avoid the saturated fat in red meat.

It's also important that you stay away from processed sugar. Sugar plays havoc with your immune system by depleting your adrenal glands, and it has also been shown to slow down the mobility of white blood cells and reduce the production of certain disease-fighting hormones. 

Finally, add fermented foods to your diet. Mounting research has shown beyond a shadow of a doubt that one of the most important components of the human immune system exists in the gut in the form of beneficial bacteria (or probiotics). These healthy bacteria support the immune system by helping to block pathogens and other toxins from being reabsorbed into your body and by minimizing the toxic byproducts of the bad bacteria in your bowels.

Two of the best fermented foods you can consume to boost your immune system are sauerkraut and yogurt. I suggest making your own sauerkraut since it's so much more delicious and healthy for you. You can also make your own yogurt using a yogurt maker, which I recommend because most of the yogurts available in grocery stores are laden with too much sugar and artificial ingredients. But if you don't want to make your own yogurt, there are two store brands that I like: Stonyfield Farm Organic Yogurt and White Mountain Foods Bulgarian Yogurt.


Regular exercise works to keep toxins moving out of your body and immune-supporting nutrients pumping in. Plus, the heat you generate while exercising can help kill pathogens while energizing your cells and metabolism for improved health.

You can raise your overall metabolic rate, improve muscle tone and energy level, enhance your mood, and promote your immune system strength with a simple, steady physical activity plan. Some simple ideas to fit exercise into your day include:

  • Go on a brisk 20–30 minute walk with a friend or your pet
  • Use the stairs instead of riding the elevator or escalator
  • Take up a low-impact sport like swimming
  • Park far from the entrance to the store and walk before and after your shopping
  • Garden

Get Good Sleep

Sleep is the critical period when your body rests and rejuvenates. Also, there are certain beneficial hormones that your body releases only when you're asleep, including human growth hormone (HGH), which boosts muscle mass and helps with cellular repair.

Studies indicate that when sleep patterns are interrupted, the levels of natural killer (NK) cells in a person's immune system are significantly reduced. Since NK cells are your immune system's first line of defense against invading pathogens and preventing cold and flu, follow these tips for getting the restorative rest you need:

  • Keep a standard bedtime and bedtime routine.
  • Keep your bedroom dark, quiet, and at a comfortable temperature.
  • Avoid caffeinated beverages and alcohol at least eight hours before bed. Also avoid less obvious sources of caffeine like chocolate, chocolate-flavored foods, soft drinks, and salt, which can act as a mild stimulant to the adrenal glands.
  • Keep work, computers, and TVs out of bedrooms.
  • Take a look at the medications you're using. One of the biggest detriments to sleep is the widespread use of both over-the-counter and prescription drugs. Even seemingly harmless sinus and nasal congestion medications can be strong nervous system stimulants that can interfere with sleep. (Never accept a new prescription from your doctor until you've given him or her a complete list of drugs that you're taking, including over-the-counter medications. Anytime you develop a new symptom after starting a new drug, consider the new drug as the culprit until you prove otherwise.)

Reduce Stress

The negative effects of stress on the immune system have been long studied and well documented. Cortisol, your body's primary stress hormone, is released when extreme conditions such as infection, intense heat or cold, surgery, and other types of trauma threaten your body. But large amounts of cortisol are also released in response to physical, chemical, or emotional stress. When your body's immune system is constantly under fire from a virtual hormone bath, it becomes weakened and more susceptible not just to the common cold and flu, but other health problems as well.

Take some time to consider what stress-reducing steps might work for your personality and life circumstances. Some excellent choices include exercise, prayer, meditation, music therapy, massage therapy, acupuncture, acupressure, and chiropractic.

Targeted Nutrients

In addition to preventive lifestyle habits, the most important thing you can do for preventing cold and flu is to give your immune system a significant boost with targeted nutrients.

Note: Not all of the following supplements may be right for you. Consider them all and choose the ones that you prefer and that you can stick with. 

  • Vitamin D. Vitamin D increases the production of a substance called cathelicidin in cells like natural killer cells, neutrophils, and monocytes. These are the cells of your immune system that attack invading pathogens. The easiest way to make sure you're getting adequate vitamin D is to get out in the sun. If you're getting your total vitamin D dose from a supplement, the following are my recommended daily maintenance levels:
      • 1,000 IU for children under 2 years old
      • 2,000 IU for children over 2 years old
      • 3,000 IU for individuals weighing 80–130 lbs.
      • 4,000 IU for individuals weighing 131–170 lbs.
      • 5,000 IU for individuals weighing over 170 lbs.
  • Vitamin C is particularly abundant in white blood cells. These cells draw in foreign invaders and then destroy them with enzymes and free radicals. Vitamin C protects the cells from being damaged during this process. It also increases the production and function of other immune system components, including natural killer cells and interferon (a biochemical messenger that promotes antiviral activity). I recommend you take 2,000 mg daily. Vitamin C is usually well tolerated, although gastrointestinal distress—particularly diarrhea—is not uncommon. You can avoid this by starting with 500 mg. Then, every three or four days, add another 500 mg until you reach 2,000 mg. If you experience any GI distress, cut back by 500 mg and stay at that dose.
  • Probiotics. Having a healthy and robust colonization of friendly bacteria in your bowels is extremely important to your immune system function. Along the long length of your intestines, you have an abundance of lymph tissue that, along with the beneficial bacteria, work to process and absorb vital vitamins and minerals while preventing toxins from being reabsorbed into your bloodstream. For this reason, many researchers are now calling the intestine the primary immune organ in the body. Another way probiotics support your immune system has to do specifically with their handling of bad bacteria. One of the major reasons bad bacteria are so detrimental to your health is that they produce numerous toxic metabolites—harmful waste products that the bad bacteria dump into your intestines and that end up circulating throughout your body, which places an enormous burden on your immune system. Healthy probiotic bacteria help to neutralize the unhealthy byproducts of bad bacteria. They also produce B vitamins and vitamin K, which are powerful antioxidants and an excellent line of defense for your body.
  • Epicor. Epicor is based on the yeast Saccharomyces cerevisiae, also commonly referred to as baker's yeast or brewer's yeast. It is one of the most researched yeasts and has been used for centuries for making bread, beer, and wine. When ingested, Epicor culture increases natural killer (NK) cell activity fourfold. This increased efficiency allows the immune system to perform at superior levels with fewer NK cells—sparing the body the stress and expenditure of having to produce more NK cells.
  • Whey protein powder is probably one of the most underutilized tools you can use to improve and protect your immune system function. It has a very high content of sulfur-containing amino acids that are necessary for the biosynthesis of glutathione. And the body's level of glutathione is a pretty good indicator of overall health and the ability of your immune system to fight off disease and counter the effects of aging.
  • Glutathione/N-Acetylcysteine (NAC). Glutathione is a tripeptide composed of three amino acids: glycine, glutamic acid, and cysteine. It's a compound that is present in every cell of your body and essential for life itself. If each of us had a "glutathione gauge" on our body, similar to the gas gauge in our car, we'd want to keep it as full as possible because it's so important to healthy immune function and healthy aging. Brussels sprouts, cauliflower, broccoli, cabbage, kale, bok choy, cress, mustard greens, horseradish, turnips, rutabagas, and kohlrabi are the richest sources. Because these aren't diet favorites of many people, I suggest that you supplement to get adequate amounts of glutathione. Glutathione is not very well absorbed in supplement form, so I recommend that you use its precursor, N-acetylcysteine (NAC). This form is metabolized or converted by the body into glutathione, and it has been proven to do a better job of raising your body's glutathione levels.
  • Propolis is the brown, waxy, sticky resin that bees collect from oozing tree buds that has amazing antiseptic, antibacterial, antifungal, antiviral, anti-amoebic, anti-inflammatory, and antipyretic (fever-reducing) properties. The recommended maintenance dosages are generally 500–1,000 mg per day in tablet and capsule form. It's rare, but some people can be allergic to bee products, so it would be wise to start with small doses of propolis first to see if you experience a problem.
  • Selenium is a trace mineral that the body incorporates into proteins to make over 25 different selenoproteins (like the enzyme glutathione peroxidase)—some of the strongest antioxidants that work to prevent cellular damage from free radicals. Selenium deficiencies cause viral mutations that could turn a harmless flu bug into a worldwide, life-threatening flu pandemic. I recommend that you get 400 mcg of selenium daily. 
Dr. David Williams

Meet Dr. David Williams

For more than 25 years, Dr. David Williams has traveled the world researching alternative therapies for our most common health problems—therapies that are inexpensive and easy to use, and therapies that treat the root cause of a problem rather than just its symptoms.

More About Dr. David Williams