With cold weather, fatigue, stress and lack of sleep, colds are quick to take advantage of weakened immune systems. Here's a look at some of the natural remedies you can use to help you bounce back.Unblock noses with essential oilsPlace two drops of antibacterial niaouli essential oil and three drops of decongestant Eucalyptus radiata essential oil onto a handkerchief or tissue and inhale as needed throughout the day.Boost the immune system's natural defensesTuck into citrus fruits like mandarins, lemons, oranges and grapefruits as well as kiwis. These are particularly rich in vitamin C, which has antiviral properties. Try to favor whole, fresh fruit. If you have a cold, you can take up to 1,000 milligrams (mg) of vitamin C per day. Between seasons, dietary intake can be boosted with a supplement of 500 mg per day. It's best to look for a supplement that combines vitamin C with vitamins E, A, zinc and selenium - always in moderate doses for a regular treatment, with a maximum 500 mg per day for sedentary lifestyles or one gram per day for keen exercisers. It is the combination of these vitamins and minerals that will ensure the desired effect. For a shock treatment, when you have a cold, for example, try taking two grams of vitamin C three times a day for a short period of time (between one and three days) then drop back to between 500 and 1,000 mg.Try a course of grapefruit seed extract as soon as symptoms appear. Dilute 15 drops in a glass of water three times a day.A hot toddy of lemon juice and honey is a highly effective remedy. Add fresh grated ginger for a warming touch.Keep microbes at bay with herbal infusionsThyme is a great choice thanks to its antibacterial properties. Echinacea can also be consumed in herbal teas to slightly relieve the intensity of symptoms like congestion, runny noses, sore throats and headaches. Lavender and yarrow can help dilate airways.Get more sleep to avoid winter tirednessColds generally last for around 10 days. To optimize recovery, try to get to bed early, rest as much as possible and keep warm. In the evening, a relaxing essential oil massage can be helpful, recommends expert Daniele Festy. Mix two drops of antiviral ravintsara essential oil, one drop of antibacterial tea tree oil, one drop of Eucalyptus radiata essential oil and one drop of rosewood essential oil with a large drop of plant-based carrier oil (apricot, almond). Apply to the sinuses, the sides of the nose, the neck and behind the ears.Make healthy winter recipes, try veggiesWinter saladTry a filling and satisfying winter salad by Melissa d'Arabian for your winter-blahs. Use high-protein Brussels sprouts as the main green (one cup has about as much protein as an egg white), coupled with nutrient-rich dark green kale. Add a bunch of crunchy, healthy goodies like walnuts, sunflower seeds, pumpkin seeds, hemp hearts and even flaxseed. The varied textures will make this dish super-satisfying. Adding a little cooked quinoa means that even ground flaxseed and hemp hearts will fit right in without a grainy mouth-feel. And a handful of pomegranate seeds adds just the right amount of tart and sweet, rounding out the flavors perfectly. Toss the whole salad with an avocado ranch dressing, whipped up in a jiffy in the blender - even this creamy, fatty dressing is a nutritious ally.Another trick is to sip warm, but not hot, drinks shortly before and after meals. Your digestive system will thank you for it. This good wintertime habit helps prepare and then assist the stomach in absorbing nutrients. It can also help prevent gas, bloating and full, heavy feelings in the stomach. Coffee should be avoided, because it suppresses appetite and irritates intestinal mucous. Tea, especially green tea, can prevent iron in food from binding effectively.EchinaceaWinter is also the ideal time to explore different varieties of vegetables. Root vegetables (carrot, parsnip, beetroot, turnip, radish, potato, sweet potato) are particularly mild on the stomach.Probiotics can shorten the duration of coldsConsuming a diet full of probiotic-rich foods does not merely help build good intestinal flora, but is also beneficial for a healthy immune system. Yogurt is a simple pleasure packed with nutrients, good bacteria and essential vitamins such as B12 that can help boost your immune system. As a result, your defenses against infections, including the pesky flu, will be stronger.