What a Doctor Takes For Cold and Flus

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If you have kids—like I do—you already know that getting sick is almost inevitable. It’s not a matter of if or even when… it’s more like how many times it’ll happen this month. So let me walk you through what I personally take—and what I skip—to get through cold and flu season with a stronger, more resilient immune system.

Supplements I Take

Vitamin D

Let’s start with vitamin D because it plays several important roles in keeping your immune system balanced and ready. A large meta-analysis of randomized trials found that vitamin D offered a modest level of protection against respiratory infections, especially for people who were deficient to begin with. But here’s the twist: newer, larger studies that include more recent trials have softened those benefits. They suggest that routine vitamin D supplements don’t provide clear, population-wide protection.

So while vitamin D isn’t the strongest evidence-based option for preventing colds or the flu, I still take it for overall health support—especially because living in Canada makes low vitamin D levels almost unavoidable in the winter. Most people do well with 1,000–2,000 IU per day. Just remember: vitamin D may slightly reduce your chances of catching a cold, but it won’t help you get over one faster. If you’re already sick, it won’t shorten your symptoms.

Zinc

Next up is zinc—specifically zinc lozenges, not regular zinc pills. While zinc in general supports immune function, lozenges offer something extra by coating the throat, which seems to interfere with the virus directly at the site of infection. This local effect helps explain why lozenges work better than swallowed zinc.

Multiple randomized trials show that zinc lozenges can shorten how long a cold lasts, but extremely high doses don’t offer extra benefits. Meanwhile, standard oral zinc supplements have mixed evidence and mainly help in areas where zinc deficiency is common, which isn’t typically the case in Canada or the U.S.

One thing I absolutely avoid is intranasal zinc sprays. They carry a real risk of permanently damaging your sense of smell, and research hasn’t shown them to work better than lozenges anyway.

For best results, use zinc lozenges—or dissolve a zinc tablet in water and sip it through the day—so zinc stays in contact with your throat. I stick to around 50 mg of elemental zinc daily once symptoms begin. Higher doses don’t work better and can cause nausea or stomach pain. Zinc won’t prevent you from catching a cold, but it can help you recover faster.

Vitamin C

Vitamin C is where things get tricky. It’s been studied for decades, and plenty of people swear by it, but the overall evidence is surprisingly unimpressive. For well-nourished people, daily vitamin C doesn’t reliably prevent colds, and it doesn’t do much to treat them either.

There are some exceptions worth noting. In people under heavy physical stress—think endurance athletes, military recruits, or intense training—vitamin C can help with prevention. For example, one large study on Korean army recruits found that taking 6 grams per day for a month lowered their risk of getting a cold by about 20%. But that’s a very specific, high-stress scenario.

When it comes to treatment, a few small studies have suggested that very high doses may shorten symptoms slightly, but larger, better-designed trials haven’t confirmed that. So vitamin C isn’t a dependable tool for cold prevention or treatment.

Still, I use it—mainly because I have little kids and almost no sleep, which definitely feels like an ongoing “high-stress environment.” In that context, I figure vitamin C might give me a small edge, and it’s cheap, safe, and easy to find.

Probiotics

Probiotics are another staple for me during cold and flu season. Certain strains—especially Lactobacillus and Bifidobacterium—have shown real potential in reducing the frequency and severity of upper respiratory infections.

A 2022 Cochrane review reported that people who took probiotics regularly were less likely to catch colds. In fact, only about three-quarters as many people got sick compared to those taking a placebo. Probiotics also slightly shortened how long symptoms lasted. While the benefits do depend on the specific strains used, the overall evidence for probiotics is stronger and more consistent than what we have for vitamin C.

The biggest drawback? Cost. A quality, multi-strain probiotic can get expensive, especially if you’re taking it daily through the winter—and even more so if you’re buying it for your kids too.

This is where fermented foods can help as a budget-friendly option. Yogurt or kefir can be useful—if they contain the right live cultures like Lactobacillus or Bifidobacterium. Kefir naturally contains several beneficial strains, making it a solid choice. But keep in mind that many fermented foods don’t contain these immune-supporting cultures, and plain yogurt without added strains won’t offer the same benefits.

Honey

Honey is another simple but powerful remedy worth keeping in your cold and flu toolkit. A meta-analysis found that honey actually performed better than standard care for easing upper-respiratory symptoms, making it an effective, inexpensive alternative to unnecessary antibiotics. For children over one year old, honey can reduce cough frequency and severity and can help them sleep better. The evidence for adults is more mixed but still promising.

I use honey regularly for my kids, especially when they’re dealing with a sore throat. It genuinely soothes irritation—and let’s be honest, sometimes kids just want something comforting. Honey checks every box: safe, effective, and delicious.

When choosing honey, the specific variety matters less than making sure you’re using real, minimally processed honey. Raw honey is ideal, and it’s best to avoid imitation syrups or heavily pasteurized products.

Supplement’s I Don’t Take

Now let’s talk about the supplements I don’t take—some of which surprise people, especially because a bit of evidence does exist for them.

Echinacea is the first one. A few studies suggest it might reduce how often you get colds or make symptoms slightly shorter. But once larger, better-designed trials came out, those effects mostly disappeared or weren’t statistically meaningful. Different species, doses, and formulas make the research incredibly inconsistent. So while echinacea might help a little, the evidence is all over the map.

The bigger reason I skip it is simple: echinacea doesn’t support my body in any meaningful way outside cold and flu season. Let me explain. I still take vitamin C, vitamin D, and zinc—even though their cold-fighting abilities aren’t amazing—because they support other aspects of health. On the days when I barely eat a real meal, snack on my kids’ leftovers, run on almost no sleep, or work late, those nutrients help with things like metabolism, skin health, cognitive function, and cardiovascular support. Even if they don’t prevent a cold, my body can still use them.

Echinacea doesn’t offer that. It isn’t a nutrient—it’s an herb used almost entirely for immune support. It doesn’t provide essential vitamins or minerals, and my body doesn’t rely on it for anything outside a possible mild immune boost. That’s the main reason I don’t bother with it.
I feel the same way about elderberry supplements and syrups. A few small studies suggest elderberry might shorten a cold or flu by a day, but the research is limited and not particularly strong.

Dr. Brian’s Approach

Here’s my practical approach, and this is coming from a naturopathic doctor: when I’m truly sick, I reach for over-the-counter medications like Tylenol Cold & Flu or DayQuil/NyQuil. In my experience, these reliably reduce symptoms enough for me to function quickly. Herbal remedies like echinacea or elderberry just don’t offer that kind of immediate relief.

At 3 a.m., when your head is pounding, your cough won’t stop, and you have to get the kids to school by 7 a.m. before heading into work, a dose of NyQuil is going to help you sleep far better than any echinacea tincture.

Many patients ask if there’s a natural alternative to medication, and I wish I could say yes. But after years of research and clinical practice, I can honestly tell you there isn’t a single supplement, herb, or functional food that fully replaces conventional medicine. I’ve explored just about everything—bovine colostrum, mushrooms, propolis—and while a few show small or early benefits, most lack strong evidence or only help specific groups of people with particular health issues. Many are expensive, too. And personally, I need something that works quickly because I don’t have time to be knocked out for days.

That’s why my approach to colds and flus is practical and grounded in reality. I stick to supplements that support immunity and overall health: vitamin D and probiotics before I get sick, and vitamin C and zinc once symptoms start. They’re not miracle cures, but they can gently support your immune system while offering other health perks. Natural options can absolutely help—you just shouldn’t expect them to wipe out symptoms overnight. Your body still needs time to fight off an infection, and during that process you’ll probably feel lousy and want to rest. And let’s be honest, when you have kids or a busy schedule, even slowing down for one day can feel impossible.

Top supplement choices

Echinacea – 4 to 8 caps / day
Elderberry – 1 tsp / day
Honey (Buckwheat) – 1 tsp as needed
Honey (Wildflower) – 1 tsp as needed
Probiotic (Align) – 1 cap / day
Probiotic (Culturelle) – 1 cap / day
Probiotic (generic) – 1 cap / day
Vitamin C (caps) – 1 cap / day
Vitamin C (Redoxon) – 1 cup / day
Vitamin C (powder) – 1 sachet / day
Vitamin D (caps) – 1 to 2 caps / day
Vitamin D (drops) – 1 to 2 drops / day
Zinc (lozenge) – 1 lozenge / day
Zinc citrate (caps) – 1 cap / day

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Citations

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