Yes, you can and should eat when you have a fever. The old saying “starve a fever” is misleading. Your body actually burns more calories when your temperature is elevated, so giving it fuel helps your immune system do its job. The real challenge is that fever often kills your appetite and slows your digestion, so what and how you eat matters more than usual.
Why Fever Increases Your Calorie Needs
A fever isn’t just uncomfortable. It’s metabolically expensive. For every degree Celsius (about 1.8°F) your temperature rises, your body’s oxygen consumption increases by 10 to 13 percent. On a typical 2,000-calorie diet, that translates to roughly 100 to 130 extra calories burned per day per degree. A fever of 102°F (about 2°C above normal) could mean your body is burning 200 to 260 additional calories daily just to maintain that elevated temperature and mount an immune response.
Skipping food entirely during this time forces your body to break down its own muscle and fat stores for energy. That’s why people often feel weak and drained after even a short illness. Eating, even in small amounts, helps preserve muscle mass and gives your immune cells the glucose and amino acids they need to function.
Why You Don’t Feel Like Eating
If the thought of food makes you queasy, that’s your immune system talking. When your body fights an infection, it releases signaling molecules that do two things at once: they raise your temperature and they suppress your appetite. These molecules act on your brain’s appetite centers and also trigger fat cells to release leptin, a hormone that tells your brain you’re full. This loss of appetite during illness is so universal across species that researchers consider it a built-in part of the immune response, not just a side effect.
Your digestion also physically slows down. A study measuring stomach emptying times found that people with fevers took an average of 118 minutes to empty their stomachs, compared to 55 minutes at normal body temperature. That’s more than twice as long. This is why large meals can sit like a brick in your stomach when you’re sick, and why small, frequent portions work much better.
What “Starve a Fever” Actually Got Wrong
The phrase “feed a cold, starve a fever” dates back centuries, and there’s a small grain of immunological truth buried in it, but not the takeaway most people assume. Researchers at the Academic Medical Center in Amsterdam found that eating a meal boosted production of a specific immune protein (interferon-gamma) by an average of 450% above baseline in healthy volunteers. Fasting, on the other hand, shifted the immune response toward a different pathway involving a separate protein (interleukin-4). These two pathways handle different types of threats.
The practical problem is that most fevers are caused by viral infections, and fighting viruses requires both arms of the immune system working together. Starving yourself doesn’t selectively help. It mostly just deprives your body of energy at the worst possible time. The medical consensus today is clear: eat when you can, even if it’s not much.
Best Foods to Eat With a Fever
The goal is to get calories, fluids, and nutrients into your body without overtaxing your sluggish digestion. Broth-based soups are the gold standard for a reason. Chicken soup or bone broth delivers hydration, sodium, potassium, and easily absorbed protein in a form your stomach can handle. It’s a meal and a drink in one.
Beyond soup, focus on these categories:
- High-water fruits: Watermelon, oranges, grapes, and cantaloupe replace fluids while providing vitamin C and natural sugars for quick energy.
- Soft, bland proteins: Skinless chicken, eggs, and fish give your immune system the amino acids it needs without being hard to digest.
- Cooked vegetables: Carrots, butternut squash, sweet potatoes without skin, and avocado are nutrient-dense and gentle on the stomach.
- Fermented foods: Yogurt and kefir support gut bacteria, which plays a significant role in immune function. Roughly 70% of your immune system is housed in your gut.
- Ginger and turmeric: Both contain natural compounds that help reduce inflammation, and ginger can ease nausea.
The old BRAT diet (bananas, rice, applesauce, toast) is fine for a day or two if your stomach is very unsettled, but it’s nutritionally limited. Harvard Health recommends moving to more nutrient-dense options as soon as your stomach can tolerate them, since protein and vitamins are what your body actually needs to recover.
Foods That Can Make You Feel Worse
When your stomach is already emptying at half its normal speed, certain foods will amplify your discomfort. Fried and fatty foods are the biggest offenders because they take the longest to digest. Spicy food can irritate an already sensitive stomach lining. Dairy products cause problems for some people during illness, particularly if diarrhea is involved. Sugary foods and drinks can worsen diarrhea by drawing water into the intestines. Caffeine and alcohol are both dehydrating, which is the opposite of what your body needs right now.
Acidic fruits like tomatoes and citrus juices (as opposed to whole citrus fruits) can also aggravate nausea in some people. If something sounds unappealing, trust your gut. Your body is generally good at steering you away from foods it can’t handle at the moment.
Hydration Matters More Than Food
If you can only manage one thing, make it fluids. Fever increases water loss through sweating, faster breathing, and elevated metabolism. Dehydration during a fever makes everything worse: headaches intensify, fatigue deepens, and recovery slows.
Water is a fine starting point, but broths and herbal teas have the advantage of providing sodium and potassium, the two electrolytes you lose most through sweat. Sweat contains an average of about 25 milliequivalents of sodium per liter. Under normal illness conditions, even moderate sweating doesn’t usually require electrolyte supplements. But if you’re sweating heavily, vomiting, or having diarrhea, replacing those electrolytes through salty broths, diluted sports drinks, or oral rehydration solutions becomes more important.
Sip steadily throughout the day rather than trying to drink large amounts at once. Your slowed digestion applies to liquids too.
Feeding Children With a Fever
Kids with fevers often refuse food entirely, and that’s usually okay for a short time. The priority for infants and toddlers is fluids, not solids. Breast milk or formula should continue as tolerated for babies. Older children can have popsicles, diluted juice, broth, or small sips of water.
The Mayo Clinic recommends calling your pediatrician if an infant misses two or more feedings in a row, hasn’t kept liquids down for eight hours, or shows signs of dehydration like fewer wet diapers, dry mouth, crying without tears, or a sunken soft spot on the head. For older kids, the same dehydration signs apply. A child who’s drinking small amounts and producing urine is generally doing fine, even if they’re not interested in solid food for a day or two.
How to Eat When Nothing Sounds Good
The practical strategy is to eat small amounts frequently rather than waiting until you’re hungry enough for a full meal, because that hunger signal may never come while you’re feverish. Try five or six mini-meals spaced a couple hours apart. A few bites of banana, a cup of broth an hour later, some crackers with a thin spread of peanut butter after that.
Temperature can matter too. Many people with fevers find room-temperature or cool foods more tolerable than hot ones, even though warm broth is a classic recommendation. Go with whatever you can actually get down. A few hundred calories of “imperfect” food is infinitely better than zero calories of the ideal recovery meal. Your body can work with surprisingly little fuel in the short term. Just don’t give it nothing at all.