The best plan of action is to take steps early on to enhance your immunity. And if you feel that a cold or flu germ is already at your doorstep, you and your family members can take steps to reduce both the symptoms and duration of the infection.

My recommendations are based on what I take preventively or to aggressively fight back against a cold or flu. Although their order of priority is subjective, the science supporting these supplements is objective and sound. In my experience, I have been able to consistently reduce a seven-day cold to just two-and-one-half days of very mild symptoms. As for the flu, it’s been some 40 years since I contracted the virus, and I haven’t gotten a flu shot in at least 20 years.

It’s crucial to start, or increase the amounts, of these supplements on the first day you experience the slightest symptoms. Waiting until the second or third day is far less effective. That’s because virus concentrations increase astronomically by then, and your immune system (which accounts for many of your symptoms) has gone into overdrive. I also suggest keeping a basic “nutritional first aid kit” at home or in the office, because if you start developing symptoms, will you have the time to rush to the store and buy the supplements you need? This kit could include N-acetylcysteine, vitamin C, zinc lozenges and other supplements depending on your own preference.

Immune-Enhancing Nutrients

N-acetylcysteine (NAC). This potent antioxidant aids the liver’s detoxification processes and helps regulate the immune response. Italian researchers gave 262 seniors either 600 mg of NAC or placebos twice daily over the cold and flu season. Of the people with laboratory-confirmed flu infections who were taking NAC, only 25 percent developed symptoms. In contrast, 79 percent of the men and women taking placeboes developed clear-cut flu symptoms, according to an article in the European Respiratory Journal.^{1 2 3} Other studies have confirmed the immune benefits of NAC.

Take: 600 mg twice daily during the cold and flu season. On the first day of symptoms, increase the amount to 2,400 to 3,600 mg daily and continue until symptoms subside.

Vitamin D

Researchers have noted that the wintertime increase in cold and flu infections appears directly related to less seasonal sun exposure and lower vitamin D production.^{4 5} Your body needs vitamin D to make a variety of germ-fighting factors, such as the important antimicrobial compound cathelicidin.^{6 7 8} Some research shows that the vitamin can reduce the risk of contracting the flu.^{9 10}

Take: 5,000 IU daily for adults, and up to 1,200 IU daily for children. Adults can also boost their vitamin D intake to 10,000-20,000 IU daily for the first several days of a cold or flu, then resume a lower dose.

Zinc lozenges

Harri Hemila, Ph.D., of the University of Helsinki, Finland, crunched data from 199 patients who took either zinc lozenges or placebos. Zinc lozenges led to significant decreases in all cold symptoms, including nasal discharge, congestion and hoarseness.¹¹ Zinc lozenges eased symptoms and reduced cold length by one day, according to a separate analysis of 1,360 people.¹²

Take: Take one lozenge every two to four hours until symptoms subside. Zinc lozenges are most effective when started at the first sign of cold symptoms.

Probiotics

From infancy on, our gut bacteria help program our immune systems. New research has shown that some specific types of probiotics can blunt cold and flu symptoms in both children and adults. Bifidobacterium bifidum eased cold and flu symptoms in stressed out college students.¹³ In a study of children in day care centers, Lactobacillus rhamnosus GG reduced upper respiratory tract symptoms.¹⁴ Still other research has shown that Bifidobacterium lactis and Lactobacillus brevis can improve cold and flu symptoms.^{15 16 17 18}

Take: What the label suggests. Any or all of the mentioned strains should provide preventive benefits when taken long term.

Vitamin C

Although critics dismiss the benefits of vitamin C, the science supports its use in reducing cold and flu symptoms, but the key is taking enough. Vitamin C seems of particular benefit to people exposed to cold and snowy weather, otherwise known as winter. Other research has shown that it reduces cold and flu symptoms among stressed children and adults. You might wonder who isn’t stressed these days—so the vitamin can benefit just about everyone.^{19 20 21 22}

Take: Studies have found that the ideal wintertime dose of vitamin C is 2 to 6 grams (2,000 to 6,000 mg) daily, but much less for small children.

Lysine

This amino acid got people’s attention decades ago when researchers at the Indiana University School of Medicine, Indianapolis, found that it inhibited the growth of herpes simplex, a virus that causes cold sores. People taking lysine had fewer infections, shorter infections and faster healing. Other studies have been conflicting, but lysine is certainly worth a try when it comes to fighting cold sores—or the common cold itself.²³

Take: 1,000 mg three times a day at the first onset of symptoms.

Herbal Relief

Echinacea

One of the most popular herbal remedies in Europe, echinacea (Echinacea spp.) works wonders when it comes to reducing the odds of catching a cold or flu, and it also seems to ease symptoms. An analysis of 14 human studies, published in Lancet Infectious Diseases, found that echinacea supplements slashed the odds of catching a cold by an impressive 58 percent. For people who did catch a cold, the herb cut its duration by a day and a half.²⁴

Take: Follow label directions, but tinctures may be more effective than capsules.

Elderberry

Elderberry (Sambucus nigra) can quickly reduce the aches, pains and tired feeling that usually accompanies the flu. In one study, Israeli researchers found that 14 of 15 people taking elderberry extract had a significant reduction in symptoms, including fever, after just two days, and 13 of the 15 patients were symptom free after three days.^{25 26 27} Most of the studies have used an elderberry syrup, not capsules.

Take: Follow label directions for use, but opt for a sugar-free syrup.

AHCC

This mushroom extract, technically known as “active hexose correlated compound,” appears to boost the activity of a family of immune cells, known as natural killer (NK) cells. NK cells are among the most powerful of immune cells and specifically target virus-infected cells and tumor cells.

Take: 1,000 mg daily.

Panax Ginseng

Ginseng has for centuries been considered a tonic and rejuvenator in Asia. A study published in the Canadian Medical Association Journal has found that North American ginseng (Panax quinquefolium) can benefit people during the cold and flu season. The study involved 232 adults who frequently caught colds. The herb slashed the length of colds by one-third, and it slightly reduced the odds of catching a cold.²⁸

Take: What the product label recommends.

Andrographis

Studies have found that this Chinese herb (Andrographis paniculata) can greatly reduce symptoms of upper respiratory infections, the very symptoms associated with the flu. Its benefits may be enhanced when combined with Eleuthero (Eleutherococcus senticosus), which was originally known as Siberian ginseng.^{29 30}

Take: Either or both of these herbs during a cold or flu, and then stop when symptoms are gone.

Lomatium

Widely used by Native Americans as food and medicine, the herb lomatium is reported to have been highly effective at preventing deaths during the 1916-1918 influenza pandemic.³¹ Traditional uses include respiratory complaints such as colds, cough, pneumonia, and asthma.³² It has been shown to have antimicrobial activity and is believed to work by enhancing the immune system.³³ A rare itchy rash may occur in a small number of people that use lomatium, which generally resolves within a few days of discontinuing use.

Take: Begin at the onset of respiratory symptoms and follow the dosing directions on the bottle.

Homeopathic Remedies

Oscillococcinum^®

Of all the homeopathic remedies, oscillococcinum (pronounced os-sil-uh-cox-suh-num) has good evidence that it can reduce flu symptoms. Homeopathy uses minute doses of substances, with low doses having a greater effect than high doses. Although the theory might sound counter-intuitive, it does make sense from the point of view of molecular biology, in which trace amounts of substances can significantly affect cell function. A respected Cochrane Collaboration review described it as a “promising” remedy and noted that it “probably reduces the duration of illness in patients presenting with influenza symptoms.”³⁴

Take: What the label suggests, starting on the first day of a cold or flu. Oscillococcinum contains extremely minute extracts of duck heart and liver, so it might not be suitable for vegetarians.³⁵

 

Not every supplement will work the same way for every person, in part because of our genetic and lifestyle differences. Still, you’ve got a pretty broad choice of natural options to help you avoid catching a cold or the flu this autumn and winter. Now is the time to start stocking your natural medicine cabinet so you are armed to beat cold and flu season.

 

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Eating Right Boosts Your Immunity

Maintaining a healthy diet—with ample amounts of veggies and fruits—is essential for a healthy immune system. That’s because most nutrients play important roles in our body’s natural resistance to infections. If you’re a senior, and you intend to get a flu shot, your body requires adequate vitamins B12 and A for the vaccine to work.^{36 37 38} As a safeguard, it might be wise to take a multivitamin supplement.

Conversely, be mindful of food choices—namely, sugary foods—that can weaken your immunity. Doctors have long known that people with poorly controlled diabetes are more susceptible to infections. Scientifically, decades old research has shown that sugary foods reduce the ability of white blood cells to fight germs.^{39 40 41}

More Ways to Survive the Cold and Flu Season

1. Wash your hands often with warm or hot soapy water.

2. Do your best to avoid touching objects, such as phones or doorknobs, that have been touched by infected people. You can wipe them down with alcohol swabs or wash your hands.

3. Resist the temptation to touch your face, nose, or ears, especially after shaking hands with someone who is infected. Again, wash your hands often.

4. Moderate exercise is good for your immunity. Over-exercising can make you more susceptible to infection.

5. People tend to close up their homes during colder months. So, occasionally open your windows or go outside for some fresh air.

6. Get enough sleep and watch your stress levels. Burning the candle at both ends weakens your immunity.

References

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