Everything you should eat when you're sick to feel better ASAP

The medicine cabinet can provide quick relief when you're suddenly slammed with a nasty cold or a pounding headache, but healing and long-term health don't start at the pharmacy. A hearty immune system begins in the kitchen—which is good news, really, because vitamin-rich foods like pineapple go down a whole lot easier than cough syrup.

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"What you put in your mouth can have an enormous influence on the digestive tract and the balance of healthy gut flora, which has been scientifically proven to affect all kinds of conditions from mental health to immune response," says Sophie Manolas, clinical nutritionist and author of The Essential Edible Pharmacy, a cookbook focused on cultivating good health.

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What exactly is a clinical nutritionist, you ask? The certified professionals work with doctors to help patients optimize their health through diet and lifestyle changes.

"I look at a patient's specific condition and determine what deficiencies might be causing it," Manolas explains. "Then I look at what they are eating in a week and figure out what I can introduce to get them the nutrients they need." From hormonal disorders to cancer, a clinical nutritionist can identify foods that can help fuel your body in its efforts to heal.

Related: Is the 80/20 diet actually a diet?

While there will be times your body needs antibiotics and other physician-prescribed treatments, produce-aisle staples can be powerhouses, too. Even a simple, everyday vegetable like cabbage is loaded with vitamin C, Manolas points out: "The beauty of these nutrients occurring abundantly in our commonly available foods is that often, nutrients are packaged together and work synergistically to have positive effects on the body."

So if Whole Foods is the new CVS, what exactly should you be filling your cart with? The specifics depend a bit on your health, but a common theme is vitamin-rich fruit and vegetables.

Keep reading for Manolas' (food) guide to good health—no pills required:

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