When you have the flu, your body needs fluids, easy-to-digest calories, and nutrients that support your immune system. Most people lose their appetite during a fever, so the priority shifts from eating full meals to getting small amounts of the right things throughout the day. Here’s what to reach for and what to skip.
Fluids Come First
Fever, sweating, and faster breathing all pull water out of your body quickly. Dehydration makes fatigue, headaches, and muscle aches worse, so staying hydrated is the single most important thing you can do nutritionally while you’re sick. Water is the baseline, but you also lose minerals through sweat. Drinks with electrolytes, like sports drinks or oral rehydration solutions, help your body actually retain the water you’re taking in rather than passing it straight through.
Warm broths are especially useful because they pull double duty: they rehydrate you while delivering vitamins, minerals, and a small amount of calories. Sipping on broth throughout the day is often easier than forcing yourself to eat when nothing sounds appealing. Herbal teas, diluted fruit juices, and coconut water are other good options. Aim to drink something at least every hour or two while you’re awake.
Why Chicken Soup Actually Works
Chicken soup isn’t just comfort food. Researchers at the University of Nebraska Medical Center found that chicken soup contains water-soluble compounds with a real anti-inflammatory effect. Specifically, the soup reduced the movement of neutrophils, a type of white blood cell that rushes to the site of infection. While neutrophils are part of your immune defense, their activity in the upper respiratory tract is also what causes much of the congestion, swelling, and discomfort you feel. By calming that activity, chicken soup may genuinely ease your symptoms.
The researchers couldn’t pinpoint exactly which compounds were responsible, but the effect held across homemade and several commercial versions. A bowl of chicken soup gives you fluid, electrolytes from the broth, a small amount of protein from the chicken, and soft vegetables that are easy on a sore throat. It’s one of the most complete flu foods you can eat.
What to Eat When Nothing Sounds Good
Loss of appetite is one of the most common flu symptoms. Your body is diverting energy toward fighting the virus, and eating can feel like a chore. The trick is to eat small amounts of calorie-dense, easy foods rather than trying to sit down for a normal meal.
Good options when your appetite is low:
- Smoothies: Blend yogurt, frozen fruit, and a banana for an easy source of calories, vitamins, and protein. You can freeze smoothies into popsicles to have between meals, which also feels soothing on a sore throat.
- Oatmeal: Soft, warm, and easy to swallow. Stir in honey for extra calories and throat-soothing properties.
- Scrambled eggs: One of the easiest sources of protein when you’re sick, soft enough to eat without much effort.
- Applesauce and bananas: Gentle on the stomach and provide quick energy from natural sugars.
- Yogurt: Delivers protein and calories in a cool, smooth form that’s easy to get down. Fermented foods like yogurt also contain probiotics, and research suggests that a healthy gut microbiome can reduce the duration and severity of respiratory infections.
If you’re really struggling to eat anything at all, nutritional supplement drinks or protein powders blended into a smoothie or stirred into soup can help bridge the gap. The goal isn’t to eat perfectly. It’s to give your body enough fuel to keep fighting.
Vitamin C and Immune-Supporting Foods
Vitamin C won’t cure the flu, but getting enough of it may reduce how severe your symptoms are and how long they last. Most studies on cold and flu recovery used about 200 mg per day, which is easy to get from food. One small orange has about 51 mg. An 8-ounce glass of orange juice delivers around 84 mg. Bell peppers, strawberries, kiwi, and broccoli are other rich sources.
You don’t need megadoses. The tolerable upper limit is 2,000 mg per day, and going above that can cause digestive problems, which is the last thing you need when you already feel terrible. Focus on eating vitamin C-rich fruits and vegetables throughout the day, or drink a couple glasses of juice if solid food isn’t happening.
Foods to Avoid While Sick
Some foods can make your symptoms feel worse. Dairy products may increase mucus production in some people, which can worsen congestion, coughing, and chest discomfort. If you notice dairy thickens things up for you, skip the milk and cheese and opt for non-dairy alternatives until you’re better. Yogurt tends to be better tolerated than milk, so you may not need to cut it out entirely.
Alcohol increases inflammation in the lungs and airways, making it harder to breathe when your respiratory system is already under stress. It also dehydrates you. Carbonated drinks can cause bloating and may make breathing feel more difficult. Sugary foods and refined carbohydrates like white bread and pastries require more metabolic effort to process, and very salty foods promote fluid retention that can contribute to a feeling of heaviness or shortness of breath. Stick to simple, whole foods and save the indulgences for when you’re feeling better.
Respiratory Flu vs. Stomach Flu
The advice above applies to influenza, which is a respiratory illness causing fever, chills, body aches, coughing, and congestion. What people call “stomach flu” is actually gastroenteritis, a completely different infection that primarily causes nausea, vomiting, and diarrhea. The two require different eating strategies.
With stomach flu, your digestive system is the battleground. The biggest risk is dehydration from vomiting and diarrhea, so fluid and electrolyte replacement becomes even more critical. Pairing electrolyte drinks with plain water works better than water alone. Start with clear liquids and work up to bland, binding foods like rice, toast, and bananas as your stomach settles. With respiratory influenza, your gut is usually functioning normally, so you have more flexibility in what you eat. The focus shifts toward calorie-dense, nutrient-rich foods that support your immune response and keep your energy up.
If you’re dealing with both respiratory symptoms and significant nausea or diarrhea, treat the stomach symptoms first. Get fluids in, keep them down, and add food gradually as you’re able to tolerate it.