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Taking vitamin C supplements might cut your chances of getting a cold in half if you're under a lot of physical stress, like running marathons, skiing, or doing tough military training in cold...
Taking vitamin C pills every day doesn't really help prevent colds for most people, according to studies with thousands of participants.
Taking zinc supplements like gluconate or acetate doesn't help reduce how long a cold lasts or how bad the symptoms are, based on a study with 281 adults who had colds.
Zinc lozenges don't help reduce how long colds last or how bad they feel, whether you catch a cold naturally or in a study where they give you a cold virus.
Taking zinc lozenges doesn't make cold symptoms less severe, according to a study with 273 people who were given cold viruses.
When adults with cold symptoms take zinc gluconate lozenges, their colds might get better faster, but this only worked in a special test setting and not with real-world colds or different zinc types.
Zinc lozenges need more than 75 mg of zinc per day to help fight colds. If you take less zinc or use lozenges with certain ingredients like citric acid, they might not work as well.
Taking zinc acetate lozenges for colds, at doses up to about 90 mg per day, didn't cause any major side effects in studies with nearly 200 people.
Zinc acetate lozenges work just as well for treating colds in people of different ages, genders, races, allergies, smoking habits, or how bad their cold is when they start.
Taking zinc lozenges helped more people get better from colds faster. For every 2 to 3 people who take them, one extra person recovers by day 5 compared to those not taking them.
Taking zinc acetate lozenges soon after cold symptoms start can help otherwise healthy adults recover from a cold about three times faster than if they didn't take them.
Even if you take zinc lozenges very soon after cold symptoms start, if the lozenges aren't made well, they still might not help you feel better faster.
If zinc lozenges dissolve too quickly in your mouth, they might not work as well as ones that dissolve slower, because studies that showed good results used lozenges that took longer to dissolve.
People who stopped taking zinc lozenges after 5 days got over their colds more slowly than those who took fake pills, which might mean stopping zinc makes cold symptoms come back a bit.
People who took zinc lozenges were much more likely to have a bad taste in their mouth than those who took fake ones, but over a third of zinc users didn't have any taste problems at all.
Taking zinc lozenges when you first feel a cold coming on doesn't really help you get better faster, according to a study on adults who get colds regularly.
A nose spray with nitric oxide can quickly kill over 99% of flu, COVID, and cold viruses in lab tests.
This claim says that taking lots of vitamin C, echinacea, garlic, or vitamin D doesn't actually help you get better from a cold, according to real studies done on people.
When you get a virus, your breathing cells need a certain chemical (chloride) to make a germ-fighting acid. If there's not enough of this chemical, your body might not fight off the virus as well.
Different zinc lozenges let your body absorb zinc differently. Some, like zinc acetate, let you use all the zinc, while others don't let you use any at all.
Honey helps people with colds feel better overall, cough less often, and have less severe coughs than usual treatments, according to medical studies.
Using saltwater nose rinses can help you get over a cold faster, cut down on how much medicine you need, and make it less likely to spread the cold to others in your home.
Rinsing your nose with salt water gives your nose cells what they need to make a natural germ-fighting chemical, which helps your body fight off viruses better.
Cells in your breathing tubes make a natural cleaning chemical that kills viruses when they try to infect you.