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How are you feeling as we careen into the holiday season? Excited? Probably. Stressed? Maybe. Are these highs and lows contributing to feeling a little run down and tired? Possibly. And you might be looking for ideas on how to best support your immune system and health as a result. And boy, are there a lot of foods, supplements and other products out there that claim to boost your immunity…often for a hefty cost. If you’ve got questions about these claims, you are not alone.

Start here (if you can read that small print): the standard disclaimer on many of those products reads: "This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure or prevent any disease."

So why are manufacturers allowed to use phrases like "boosts immune function" and "supports immune health?" I know this is confusing (and mildly annoying), so we’ll do our best to explain.

Boosting immunity is a job for vaccines. They help program your immune system to fight off a specific beastie and the illness that can result from its infection (like the flu shot before each flu season).

Immune support typically describes nutrients necessary for a healthy immune system. It's true that a deficiency of necessary functional nutrients can cause poor immune function. But that doesn't mean a person with normal nutrient levels can expect supplements to improve their immune system. So, can products marketed as immune boosters actually “boost” immunity?

Unless you have a deficiency in a key nutrient, such as vitamin C or zinc, the short answer is no.

Results of studies looking at various products marketed toward colds and other similar infections have been mixed at best. Even when taking a particular supplement or product was linked to reduced severity or duration of an infection, there's no proof that the supplement boosted overall immune function.

This also goes for individual food items. As Karen will talk about this week, it's the overall quality of your diet, not individual foods, that matters most. There are exceptions for certain specific illnesses where their treatments can affect how well the immune system works, so people living with these conditions may need additional help from medications and therapies. This is really the only definition of immune boosting that is fact-based. But those supplements and other products? Leave those on the shelf and use that money for something else!