When you have the flu, your body burns through more calories and fluids than usual just fighting the infection. Fever alone increases your metabolic rate with every degree your temperature rises. The best foods to eat are ones that deliver hydration, easy calories, and nutrients without upsetting a sensitive stomach: brothy soups, simple starches, fruits, yogurt, and plenty of liquids.
Why Eating Matters Even When You Don’t Feel Like It
A fever speeds up your metabolism, which means your body demands more energy at exactly the moment you least feel like eating. Skipping meals entirely can leave you weaker and slower to recover. You don’t need to force down a full plate, but getting some calories and nutrients in throughout the day gives your immune system the fuel it needs to do its job.
Small, frequent meals work better than three large ones when you’re sick. If a full bowl of anything sounds overwhelming, start with a few spoonfuls every hour and build from there.
Chicken Soup Genuinely Helps
Chicken soup isn’t just comfort food tradition. A well-known study published in the journal CHEST found that chicken soup inhibits the movement of white blood cells called neutrophils in a concentration-dependent way. Neutrophils are part of the inflammatory response that causes congestion, sore throat, and that general “everything hurts” feeling. By slowing their migration, chicken soup acts as a mild anti-inflammatory, which can ease upper respiratory symptoms.
The researchers tested the vegetables and chicken separately and found that each ingredient contributed to the effect. The broth also delivers salt and water, two things your body is losing rapidly through sweat and fever. If you’re making it from scratch, include plenty of vegetables and keep the broth on the saltier side. Store-bought versions work too.
Fluids Are More Important Than Food
Fever, sweating, and faster breathing all pull water out of your body. Dehydration makes headaches worse, thickens mucus, and can leave you feeling dizzy on top of everything else. Sipping water throughout the day is more effective than drinking large amounts at once, because your body absorbs smaller volumes more efficiently.
Plain water is fine, but you’re also losing electrolytes (sodium, potassium, and other minerals your muscles and nerves need to function). Broth, diluted fruit juice, coconut water, and oral rehydration drinks all help replace what you’re losing. Popsicles and ice chips count too, especially if swallowing is painful.
The CDC recommends avoiding alcohol and caffeinated drinks like coffee, tea, and cola while you’re feverish. Both can worsen dehydration at a time when staying hydrated is critical.
Best Foods When Your Stomach Can Handle Them
If nausea or stomach symptoms are part of your flu, start with bland, easy-to-digest foods. The classic BRAT diet (bananas, rice, applesauce, toast) is a reasonable starting point for the first day or two, but Harvard Health notes there’s no reason to limit yourself to just those four items. Other gentle options include oatmeal, boiled potatoes, crackers, unsweetened dry cereal, and brothy soups.
Once your stomach settles, add foods with more nutritional value so your body has what it needs to recover:
- Skinless chicken or turkey: lean protein without heavy fat
- Cooked carrots, squash, or sweet potatoes: soft, easy to digest, and rich in vitamins
- Eggs: a good protein source that’s gentle on the stomach
- Avocado: calorie-dense and bland enough to tolerate
- Fish: light protein that won’t sit heavy
The goal is to move beyond crackers and toast as soon as you’re able, because those foods alone don’t provide the protein and micronutrients your immune system is burning through.
Honey for Cough Relief
If a persistent cough is one of your worst symptoms, honey can help. Clinical studies have found that honey works about as well as common over-the-counter cough suppressants. A half teaspoon to one teaspoon (2.5 to 5 milliliters) is enough. You can take it straight, stir it into warm water or tea, or add it to diluted juice.
One important exception: honey should never be given to children under one year old due to the risk of botulism.
Yogurt and Probiotic Foods
Fermented foods like yogurt, kefir, and miso contain beneficial bacteria that support your gut, which plays a larger role in immune function than most people realize. A clinical trial in children with respiratory infections found that a daily probiotic mixture shortened fever duration by two days compared to placebo (three days versus five). While that study used a supplement rather than food, yogurt and kefir deliver similar bacterial strains.
Choose plain or lightly sweetened varieties. Heavily sweetened yogurts work against you (more on sugar below). If dairy doesn’t appeal to you while sick, miso soup is another good option that also delivers salt and warm broth.
Nutrients That Support Your Immune System
Two nutrients get the most attention during cold and flu season: vitamin C and zinc.
Vitamin C taken regularly (before getting sick) reduces the duration of colds by about 8% in adults and 14% in children. It also lessens symptom severity. However, research from the Linus Pauling Institute shows that starting vitamin C supplements after symptoms begin doesn’t appear to help. Your best bet is to eat vitamin C-rich foods as part of your regular diet: citrus fruits, strawberries, bell peppers, and kiwi. When you’re already sick, these foods still provide hydration and easy calories even if the vitamin C benefit is modest at that point.
Zinc is a different story. High-dose zinc lozenges (more than 75 mg per day) started within 24 hours of symptom onset can shorten the duration of illness. Zinc nasal sprays, on the other hand, don’t appear to help and carry a risk of permanently damaging your sense of smell. If you prefer food sources, oysters, red meat, pumpkin seeds, and chickpeas are all high in zinc, though it’s difficult to hit therapeutic doses through food alone during an acute illness.
What to Avoid While You’re Sick
Foods high in added sugar are the biggest thing to cut back on. High blood sugar increases the production of inflammatory proteins in your body, forces white blood cells to work harder, and can disrupt the balance of bacteria in your gut. All of this weakens your immune response at exactly the wrong time. Sugary sodas, candy, pastries, and heavily sweetened drinks are worth skipping until you’re better.
Greasy, heavy, or spicy foods can also make nausea worse and are harder to digest when your system is already under stress. Stick with simple, mild flavors until your appetite comes back fully.
As for dairy, you may have heard that milk increases mucus production. It doesn’t. Research going back decades, including studies referenced by the Mayo Clinic, has found no connection between dairy and phlegm. What does happen is that milk and saliva mix to create a slightly thick coating in your mouth and throat that feels like mucus but isn’t. If dairy doesn’t bother your stomach, there’s no reason to avoid it.
A Simple Sick-Day Eating Plan
You don’t need to overthink this. A practical approach looks something like this: sip fluids constantly, aim for a small snack or mini-meal every two to three hours, and prioritize broth-based soups, simple starches, lean protein, and soft fruits. If you can only manage one thing, make it fluids with electrolytes. If you can manage two, add chicken soup. Everything else builds on that foundation.
As your appetite returns over the next few days, gradually bring back normal meals with more variety. Your body has been burning extra energy fighting the virus, and replenishing protein, vitamins, and calories speeds up the tail end of recovery.