It's happened, and there's no denying it: You've got a cold, and it's awful. Aches and pains, stuffy nose, sore throat and exhaustion so deep that you wake up from a nap wishing for another.

So, what can you do now that you're already sick? You know if you go to a doctor, you'll will just be sent home with instructions for rest and hydration (which are both good and important pieces of the get-well-faster puzzle). But beyond that? You aren't totally helpless, and while you're going to be sick, there are some natural remedies — with some good science behind them — that can make you more comfortable, help you get better a bit faster, and most importantly, prevent a cold from turning into something worse.

Gargle with water

Surprisingly enough, a simple thrice-daily gargle with plain water resulted in statistically significant reductions in virus infection and colds in a small study, compared to non-gargling control subjects. It also can't hurt that a good gargle will clear extra food particle from the mouth, resulting in less bad breath and fewer bacteria acting on your tooth enamel.

Nasal irrigation serves a similar function as gargling — by clearing the nasal passages of viruses and particles — and can be especially useful for people who have regular sinus issues and sinusitis.

Take your vitamin D

Woman sick on the couch Vitamin D is linked to increased immune function, so if you're too sick to go outside and get your daily dose from the sun, consider taking a vitamin supplement. (Photo: baranq/Shutterstock)

Vitamin D (which most of us don't get enough of from our food) is an overall immune booster and can possibly reduce your chance of getting the flu (and other diseases). According to the Harvard School for Public Health, which looked at a number of studies involving vitamin D: if you live north of the latitudinal line that runs from San Francisco to Philadelphia, or don't get a 15-minute dose of sunshine a day, you are likely vitamin D deficient (African-Americans, and those who are overweight or obese are at higher risk for deficiency).

While we all know that vitamin D is important for building bones, its links to immune function — including colds and flu, but also to lower cancer rates and autoimmune diseases — is a newer research area and is currently being studied.

Even with research ongoing, this excerpt from the Harvard Public Health analysis of the vitamin should convince even the most wary that a daily dose of D is worth taking, and not just to keep a cold at bay: "A combined analysis of multiple studies found that taking modest levels of vitamin D supplements was associated with a statistically significant 7 percent reduction in mortality from any cause. The analysis looked at the findings from 18 randomized controlled trials that enrolled a total of nearly 60,000 study participants; most of the study participants took between 400 and 800 IU of vitamin D per day for an average of five years."

Since vitamin D supplements are low-risk, you don't have to worry about getting too much if you stay within general guidelines. Otherwise healthy adults should aim for 1,200-2,000 IUs of vitamin D a day — look for supplements labeled D3 (cholicalciferol). Of course, you can also get your body to make its own vitamin D by getting sunshine every day (sunblock will prevent this physiological process), but that can be a challenge for many.

Get your vitamin C and zinc, too

Man sick with a cold Stress and illness can deplete your body of vitamin C, but keeping that level high can help fight off a cold. (Photo: STUDIO M/Shutterstock)

Vitamin C is another vitamin that has been shown, in repeated studies, to help the body heal from — and more effectively fight off — viruses. Because stress and illness deplete the blood of normal vitamin C concentrations, keeping them high can mean the difference between getting a cold or fighting it off, or a way to keep your illness from developing into something more serious. Your body flushes extra vitamin C, so you don't have to worry about overdosing.

Similarly to vitamin C, low blood levels of zinc can impact immune function: "... trials document that adequate intakes of vitamin C and zinc ameliorate symptoms and shorten the duration of respiratory tract infections including the common cold. Furthermore, vitamin C and zinc reduce the incidence and improve the outcome of pneumonia, malaria, and diarrhea infections, especially in children in developing countries."

Look to essential oils

Tea tree oil and eucalyptus oil aerosols or vapors not only make your space smell fresh naturally, but can reduce viral activity in your home or workspace. According to an Australian study, "Tea tree and eucalyptus oils are capable of inactivating airborne viruses: The efficiency is also high when vapors of these oils are used." And of course, they work well for opening air passages when you are congested for any reason, offering immediate relief.

Steaming face over bowl Add a few drops of essential oils to a bowl of steaming water and inhale the vapor. (Photo: Image Point Fr/Shutterstock)

Here are 5 easy ways to utilize these natural virus-fighting effects:

  • Simmer some tea tree oil in water on your stove.
  • Buy a vaporizer for use in a specific room.
  • Inhale the vapor by putting your face over a bowl of steamy water (be careful it's not too hot) with added oils.
  • Breathe through a warm damp towel soaked with a few drops of eucalyptus or tea tree oil.
  • Use a dust mask in this way to get a precise dose or be able to get relief when you are on the go.

Eat your way well

Homemade chicken soup has been found to reduce inflammation, which directly helps upper respiratory issues; a traditional recipe will include vegetables, which can also help. (Look for organic chicken to ensure that you aren't consuming unnecessary pesticides, drugs or hormones.) Consider adding some fresh garlic, which stimulates the immune system, to your soup (or making some garlic bread to go with your soup).

And don't forget to follow doctors' (and mom and dad's) advice: get plenty of fluids and plenty of rest if you feel crummy — and keep your germs at home.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.