When your baby is sick, the most important thing to focus on is fluids, not food. Babies lose water fast during illness, especially with vomiting or diarrhea, and preventing dehydration matters more than getting calories in. What you offer and how you offer it depends on your baby’s age, whether they’ve started solids, and what symptoms they’re dealing with.
Fluids Come First
For babies under 12 months, the best fluids during illness are breast milk, properly mixed formula, or an oral rehydration solution like Pedialyte. These provide the right balance of electrolytes and sugar to replace what’s being lost. Avoid giving plain water (unless it’s used to mix formula), fruit juice, broth, tea, or any sugary drinks. These can actually pull more water into the intestines and make diarrhea worse.
If your baby is vomiting, wait about 30 minutes after the last episode before offering fluids again. Then start slow: 1 to 2 teaspoons (5 to 10 mL) every 5 to 10 minutes using a spoon or syringe. This feels painfully slow when your baby seems thirsty, but small, frequent sips are far less likely to come back up than a full feeding. If your baby keeps that down for an hour, you can gradually increase the amount.
For babies 6 months to 4 years on an oral rehydration solution, a good starting target is 5 mL every 5 minutes for the first hour. If nothing comes back up, double that to 10 mL every 5 minutes for the next hour.
Why Breast Milk Is Especially Helpful
Breast milk does double duty during illness. It hydrates and delivers antibodies, proteins, fats, sugars, and even white blood cells that actively fight infection. These immune components go to work in your baby’s gut before nutrients are even absorbed into the bloodstream. Breast milk also supplies a steady stream of probiotics that support the gut lining, which takes a hit during stomach bugs.
If you’re breastfeeding, nurse more often but for shorter sessions. This keeps fluid intake steady without overwhelming a sensitive stomach. There’s no need to switch to a rehydration solution unless your baby is refusing the breast or showing signs of dehydration.
Formula-fed babies should continue on their regular formula, mixed at the normal concentration. Don’t water it down. If your baby can’t tolerate a full bottle, offer smaller amounts more frequently, just as you would with breast milk.
What to Offer Once They’re Ready for Food
If your baby has started solids (typically around 6 months), you don’t need to withhold food. The old advice to stick with the BRAT diet (bananas, rice, applesauce, toast) is outdated. The American Academy of Pediatrics no longer recommends it for children because it’s too low in protein, calcium, fiber, and B12. Following it for more than 24 hours can actually slow recovery by depriving your baby’s body of the nutrients it needs to heal.
Instead, offer your baby their normal foods as tolerated. Good options include soft, nutrient-dense choices that are easy on the stomach:
- Mashed bananas or avocado for gentle calories and potassium
- Cooked sweet potato or carrots for vitamins without much fiber
- Plain yogurt (no added sugar) for protein and probiotics
- Soft scrambled eggs for protein that’s easy to digest
- Well-cooked rice or oatmeal for bland, starchy energy
- Shredded chicken or soft tofu for protein when they’re up for it
Keep portions small. A few bites at a time is fine. Your baby’s appetite will likely be reduced, and that’s normal. The goal is to offer food without pressure. As they feel better, they’ll eat more on their own.
Foods and Drinks to Avoid
Some foods can make symptoms worse, particularly diarrhea. Skip fried, greasy, or heavily processed foods. Avoid full-strength fruit juice, especially apple juice, which can loosen stools. If dairy seems to be making diarrhea worse or causing gas and bloating, temporarily cut back on milk-based foods (plain yogurt is usually still tolerated because fermentation breaks down some of the lactose).
Gas-producing vegetables like broccoli, peppers, beans, peas, corn, and leafy greens are best saved for after recovery. Same goes for high-fiber fruits like berries and prunes. These are all healthy under normal circumstances, but during active diarrhea they can add to discomfort.
How to Spot Dehydration
Dehydration is the real danger when a baby is sick, and it can develop quickly. Watch for these signs:
- Fewer wet diapers than usual (fewer than four in 24 hours is a red flag)
- A sunken soft spot on top of the head
- Sunken eyes or a dry mouth
- Few or no tears when crying
- Unusual drowsiness or irritability
If your baby shows any of these signs, contact your pediatrician promptly. Mild dehydration can often be managed at home with careful rehydration, but moderate to severe dehydration may need medical attention. A baby who refuses all fluids for several hours, or who can’t keep anything down despite the slow syringe method, needs to be seen.
When Appetite Doesn’t Bounce Back
Most babies eat less for a few days during and after an illness. This is expected. Their bodies are redirecting energy toward fighting infection, not digesting food. As long as they’re taking in fluids and wetting diapers at a reasonable rate, a temporary dip in solid food intake isn’t cause for alarm.
Once the worst symptoms pass, gradually reintroduce their full range of normal foods. Their body needs the protein, fat, and vitamins to rebuild. Most babies return to their normal eating patterns within a few days of feeling better, sometimes with a surge in appetite as they make up for lost ground.