Breastfeeding is one of the most nurturing experiences a mother can offer her baby. It supports the infant’s immune system, promotes healthy growth, and strengthens the emotional bond between mother and child. However, a mother’s diet during this stage plays a critical role—not just in her own well-being, but in the health and comfort of her nursing baby. While there are many nutrient-rich foods that support lactation, there are also certain foods and beverages that may cause complications if consumed. This comprehensive guide explores what not to eat while breastfeeding to help mothers make informed dietary decisions for both themselves and their babies.
Why Maternal Diet Matters During Breastfeeding
When you’re breastfeeding, your body draws energy and nutrients from your diet to produce breast milk. Therefore, anything you consume has the potential to affect your milk, either directly or indirectly. While the body works hard to filter harmful substances, some pass through into breast milk more easily than others. These may influence your baby’s digestion, sleep patterns, or even cause allergic reactions.
Additionally, your nutritional intake impacts your own energy levels, recovery from childbirth, and mental health. The goal is to maintain a balanced diet that nourishes you while minimizing the risk of adverse effects on your infant.
Foods and Substances to Avoid While Breastfeeding
While no food is entirely off-limits for every nursing mother, certain items should be limited or avoided due to their potential side effects. Individual tolerance varies, but the following categories represent the most commonly problematic foods and substances.
1. High-Mercury Fish
Fish is an excellent source of omega-3 fatty acids, protein, and essential vitamins. However, some fish contain high levels of mercury—a toxic metal that can impair your baby’s developing nervous system.
Fish to avoid:
- Shark
- Swordfish
- King mackerel (not to be confused with Atlantic or Spanish mackerel)
- Tilefish from the Gulf of Mexico
- Bigeye tuna (often found in sushi)
The U.S. Food and Drug Administration (FDA) recommends that nursing mothers choose fish with lower mercury levels, such as salmon, sardines, trout, and canned light tuna. It’s safe to consume 2–3 servings per week of low-mercury fish to support brain development in infants.
2. Excessive Caffeine
Caffeine is a stimulant that passes into breast milk. While small amounts are generally considered safe, consuming too much can lead to irritability, poor sleep, and fussiness in babies, especially newborns whose systems are still immature.
How Much Is Too Much?
The American Academy of Pediatrics suggests that mothers limit their caffeine intake to no more than 300 milligrams per day—about 2–3 cups of coffee, depending on the strength. However, some infants are more sensitive and may react to even smaller amounts.
Tips for managing caffeine:
- Drink caffeine immediately after nursing to allow time for it to metabolize before the next feeding.
- Choose decaffeinated coffee or herbal teas labeled safe for nursing mothers.
- Be aware of hidden caffeine in soft drinks, energy drinks, chocolate, and certain medications.
3. Alcohol Consumption
Many new mothers are curious about whether they can enjoy an occasional drink while breastfeeding. While an occasional small amount may not be harmful, alcohol passes directly into breast milk and can affect an infant’s development, motor skills, and sleep patterns.
What Happens When You Drink Alcohol?
Contrary to myth, alcohol does not increase milk production. In fact, it may inhibit let-down reflex and reduce the amount of milk a baby consumes during a feed. Even small doses can impair an infant’s ability to process alcohol due to their underdeveloped liver.
The safest approach: avoid alcohol or use a “pump and dump” strategy if consumed. However, pumping does not speed up alcohol elimination—your body naturally processes alcohol over time. As a rule of thumb, wait at least 2 hours per standard drink before nursing again.
Avoid:
- Beer, wine, or hard liquor in large quantities
- Drinks mixed with alcohol, such as cocktails
- Alcohol-based extracts (e.g., vanilla extract) in large amounts
4. Excessive Spicy or Gassy Foods
Spicy foods or those known to cause gas—like onions, garlic, broccoli, cabbage, and beans—are often debated among breastfeeding mothers. While many babies are unaffected, some may become fussy or gassy after a mother eats these foods.
Understanding Infant Sensitivity
The primary concern with these foods is not the flavor itself, but how your baby reacts. Some infants may develop:
- Colic symptoms
- Gas and bloating
- Increased spitting up
If your baby shows signs of discomfort after you consume such foods, try eliminating them one at a time to identify triggers. Note: Flavor variety in breast milk may actually help babies accept solid foods later on, so many experts suggest not avoiding these unless a clear reaction is observed.
5. Dairy Products and Common Allergens
Dairy is a major source of calcium and protein for nursing mothers, but it can be problematic for some infants. Cow’s milk protein can pass into breast milk and cause allergic reactions or digestive issues in babies.
Symptoms of a Milk Allergy in Babies
Common signs include:
- bloody or mucousy stools
- frequent vomiting
- skin rashes or eczema
- excessive crying and gas
- poor weight gain
If you suspect a dairy allergy, consult with your pediatrician. Elimination of dairy from your diet for a short trial period (typically 2–3 weeks) under medical supervision may help confirm the diagnosis. Be mindful of hidden dairy in processed foods, such as casein or whey.
Other potential allergens that may affect babies:
- soy
- eggs
- peanuts
- wheat
- tree nuts
However, current guidelines suggest that early maternal exposure to allergens does not increase allergy risk and may even reduce it. Always discuss any elimination diet with a healthcare provider.
6. Herbal Supplements and Teas
Many nursing mothers turn to herbal remedies to boost milk supply, relieve stress, or combat fatigue. While some herbs like fenugreek and fennel are traditionally considered safe, others can be harmful.
Herbs to avoid while breastfeeding:
- Comfrey – contains liver-toxic pyrrolizidine alkaloids
- Sage – may reduce milk supply due to its drying properties
- Parsley (in large amounts) – also believed to decrease milk production
- Yarrow – potential risk of contamination and unknown effects on the baby
Additionally, herbal teas marketed for relaxation or weight loss may contain unknown ingredients or diuretics that could affect hydration and milk production. Stick to well-researched, lactation-safe herbs and always disclose supplement use with your doctor.
7. Undercooked or Raw Foods
Food safety is paramount during breastfeeding. Consuming raw or undercooked foods increases the risk of bacterial infections like Salmonella, Listeria, or E. coli, which can severely affect a mother’s health and, in rare cases, pass to the baby during care.
Avoid:
- Raw seafood (e.g., oysters on the half-shell, rare tuna in sushi)
- Undercooked meat or poultry
- Raw eggs (found in homemade mayonnaise, Caesar dressing, or some desserts)
- Unpasteurized dairy (such as raw milk or soft cheeses like Brie, Camembert)
These pathogens do not typically enter breast milk, but if the mother becomes ill, her ability to nurse and care for her baby decreases, and the infant could be exposed through close contact.
8. Highly Processed and Sugary Foods
While it’s okay to indulge occasionally, consistently consuming ultra-processed foods, high-sugar snacks, and trans-fat-laden meals can have long-term consequences.
Why avoid heavily processed foods?
- They provide empty calories with little nutritional value.
- They may increase inflammation, fatigue, and postnatal depression risk.
- They often contain additives and preservatives with unknown long-term effects on babies.
Instead, focus on whole grains, lean proteins, fruits, and vegetables to sustain energy and support milk quality.
Foods That May Affect Milk Supply
While most foods don’t drastically alter milk production, some may have hormone-disrupting or “drying” effects that reduce lactation.
Parsley and Peppermint (in large amounts)
Known for their culinary flavor, both fresh herbs are generally safe in small quantities. However, large amounts of peppermint—especially as essential oil or strong tea—can inhibit prolactin, the hormone responsible for milk production. Parsley, particularly in juice or supplement form, has been traditionally used to suppress lactation.
Sage and Oregano
Sage contains compounds that may decrease milk supply. It’s often used intentionally by mothers to wean their babies. Similarly, large doses of oregano might have a suppressive effect, though research is limited.
Excessive Fennel (in supplement form)
Fennel tea is often used to enhance milk production. However, in high doses, it may have estrogenic effects and potentially disrupt the hormonal balance. Moderate use as tea is usually fine, but concentrated extracts should be approached with caution.
Culturally Influenced Foods to Monitor
Some foods widely consumed in certain cultures may affect infants differently. For example:
- Garlic-heavy dishes: While delicious, some babies may refuse to nurse if the milk tastes strongly of garlic. Others may tolerate or even enjoy it.
- Exotic tropical fruits: Fruits like papaya or jackfruit, especially unripe ones, contain enzymes that might trigger sensitivities in some babies.
- Spicy Indian or Mexican cuisine: Capsaicin, the compound that gives peppers their heat, can enter breast milk and may lead to fussiness in sensitive infants.
Observe your baby’s behavior and discuss any dietary changes with a pediatric dietitian if concerns arise.
Common Myths About Breastfeeding and Diet
Misinformation can lead to unnecessary dietary restrictions. Let’s debunk some common myths.
Myth 1: “All Spicy Foods Cause Gas in Babies”
Reality: There’s no strong scientific evidence that spicy food directly causes gas in babies. The digestive systems of infants react more to proteins in allergens than to spices.
Myth 2: “You Must Drink Milk to Make Milk”
Reality: While calcium is essential, it doesn’t have to come from dairy. Plant-based sources like fortified soy milk, leafy greens, almonds, and tofu can provide adequate calcium for lactating women.
Myth 3: “If Food Tastes Funny, It Will Make the Baby Fussy”
Reality: Flavor changes in breast milk are normal and natural. In fact, babies exposed to diverse flavors in utero and through breast milk often adapt more easily to solid foods. Only persistent fussiness or medical symptoms indicate a problem.
Guidelines for a Balanced Breastfeeding Diet
Rather than focusing only on what not to eat, it’s equally important to know what to prioritize.
Nutrients essential during breastfeeding:
- Calcium: 1,000 mg/day (dairy, fortified plant milks, greens)
- Iron: Important due to blood loss during childbirth (lean meats, legumes, spinach)
- Vitamin D: Helps with calcium absorption and immune function
- Omega-3 (DHA): Supports baby’s brain and eye development (fatty fish, flaxseeds, walnuts)
- Folate: Vital for DNA synthesis and repair (leafy greens, citrus, fortified grains)
- Hydration: Breastfeeding increases fluid needs—aim for 8–10 glasses of water daily
A sample daily diet plan could include:
- Breakfast: Oatmeal with flaxseeds, banana, and fortified almond milk
- Mid-morning: Greek yogurt with berries and a sprinkle of chia seeds
- Lunch: Grilled salmon salad with spinach, avocado, and olive oil dressing
- Afternoon snack: Whole grain toast with natural peanut butter and apple slices
- Dinner: Quinoa-stuffed peppers with brown rice, black beans, and steamed broccoli
- Evening: Herbal tea (non-caffeinated, lactation-safe) and a small handful of nuts
When to Consult a Professional
Every mother and baby pair is unique. If you notice any of the following, speak with a healthcare provider:
- Infant develops persistent rashes, diarrhea, or breathing issues
- Baby refuses the breast or shows signs of severe discomfort
- You’re considering a major dietary change or elimination diet
- You’re using medications or supplements not approved by a doctor
A lactation consultant, registered dietitian, or pediatrician can help assess the root cause and offer tailored recommendations.
Final Thoughts: Finding Your Balance
Motherhood is a journey filled with choices—especially when it comes to feeding your baby. While the list of foods to limit or avoid during breastfeeding may seem daunting, the goal is not perfection but mindful awareness.
You don’t have to eliminate entire food groups unless you notice a clear and consistent reaction in your baby. The human body is resilient, and breast milk remains the gold standard for infant nutrition—regardless of minor dietary fluctuations.
By focusing on a diverse, whole-foods-based diet, staying well-hydrated, and avoiding known risks like high-mercury fish and alcohol, you’re giving both yourself and your baby the foundation for long-term health. Trust your instincts, keep an eye on your baby’s responses, and don’t hesitate to seek guidance when in doubt.
Breastfeeding is not about dietary restrictions—it’s about connection, nourishment, and empowerment. With informed choices, you can enjoy both your favorite foods and a thriving, happy baby.
Why should I avoid alcohol while breastfeeding?
Consuming alcohol while breastfeeding can pose risks to your baby’s development and overall health. Alcohol passes into breast milk and can affect your infant’s sleep patterns, motor development, and overall growth. Even small amounts may disrupt your baby’s ability to learn and develop normally, especially during critical periods of brain development. Since babies metabolize alcohol much more slowly than adults, it can remain in their system longer, increasing the potential for harm.
To minimize risk, it’s best to avoid alcohol altogether while breastfeeding. If you do choose to drink, it’s recommended to wait at least two to three hours per standard drink before nursing to allow your body time to clear the alcohol. Pumping and dumping will not speed up this process, as alcohol leaves milk at the same rate it leaves your bloodstream. Planning ahead by nursing or pumping before alcohol consumption can help ensure your baby receives alcohol-free milk.
Are high-mercury fish harmful during breastfeeding?
Yes, high-mercury fish can be harmful to both breastfeeding mothers and their babies. Mercury is a toxic metal that accumulates in certain fish, and when consumed, it can pass into breast milk. Exposure to high levels of mercury can impair a baby’s developing nervous system, leading to cognitive delays, motor skill issues, and learning difficulties. Large predatory fish like shark, swordfish, king mackerel, and tilefish are known to contain elevated levels of mercury and should be avoided.
Instead, opt for low-mercury fish that provide beneficial omega-3 fatty acids without the health risks. Examples include salmon, sardines, trout, and cod. The U.S. Food and Drug Administration (FDA) recommends that breastfeeding women consume 8 to 12 ounces of low-mercury fish per week to support both maternal and infant health. Always be mindful of local fish advisories if consuming fish from local waters.
Can caffeine affect my breastfed baby?
Caffeine consumed by a breastfeeding mother can pass into breast milk and may affect a baby’s sleep and behavior. Some infants, especially newborns and premature babies, are more sensitive to caffeine and may become fussy, jittery, or have trouble sleeping after nursing if their mother has consumed large amounts. Since caffeine has a longer half-life in infants, it can accumulate in their system more easily than in adults.
It’s generally safe to consume moderate amounts of caffeine—up to 200 to 300 milligrams per day, which is roughly equivalent to one to two cups of coffee. To reduce potential effects, consider drinking caffeine shortly after nursing to allow more time for it to clear from your system before the next feeding. Watch your baby for signs of sensitivity, and if noticed, consider cutting back further or switching to decaffeinated beverages.
Should I avoid highly processed foods while breastfeeding?
Highly processed foods often contain unhealthy fats, excess sodium, added sugars, and artificial ingredients, which may not support optimal nutrition for breastfeeding mothers. These foods can contribute to poor maternal health, such as weight gain, high blood pressure, and reduced energy, which indirectly affects the quality of breast milk. Additionally, a diet high in processed foods may lack the essential nutrients your baby needs for proper growth and development.
While occasional processed foods are unlikely to harm your baby, relying on them regularly can result in nutrient deficiencies for both mother and child. Instead, focus on whole, nutrient-dense foods like fruits, vegetables, whole grains, lean proteins, and healthy fats. These foods support milk production, energy levels, and overall well-being. A balanced diet not only benefits your health but also positively influences the nutritional content of your breast milk.
Is it safe to eat raw or undercooked foods while breastfeeding?
Consuming raw or undercooked foods, such as raw eggs, unpasteurized dairy, or sushi made with raw fish, increases the risk of foodborne illnesses like salmonella, E. coli, and listeria. While these infections primarily affect the mother, they can indirectly impact the baby. A sick mother may produce less milk, have difficulty nursing, or spread bacteria through close contact. Severe infections may even require medications that could affect breastfeeding.
To protect yourself and your baby, avoid raw or undercooked animal products. Always ensure eggs are fully cooked, meats are properly heated to safe internal temperatures, and dairy products are pasteurized. When it comes to fish, especially for sushi, opt for cooked varieties or those from reputable sources. Proper food handling and hygiene are critical during breastfeeding to maintain maternal health and ensure uninterrupted, safe nursing.
Do allergenic foods like peanuts need to be avoided during breastfeeding?
In most cases, there is no need to avoid common allergenic foods like peanuts, tree nuts, eggs, or dairy while breastfeeding unless you or your baby have a known allergy. Current research suggests that early exposure to allergenic foods through breast milk may actually help reduce the risk of food allergies in infants. Restricting these foods unnecessarily can limit your nutrition and reduce dietary variety, which is important for milk quality.
However, if your baby shows signs of an allergic reaction—such as rash, eczema flare-ups, vomiting, diarrhea, or difficulty breathing—consult your pediatrician. They may recommend eliminating certain foods from your diet to see if symptoms improve. Always work with a healthcare provider before making significant dietary changes, especially if there’s a family history of allergies.
Can herbal supplements interfere with breastfeeding?
Some herbal supplements can negatively affect milk supply or pass into breast milk and impact your baby’s health. Herbs like sage, parsley in large amounts, and peppermint may reduce milk production, while others such as coltsfoot, comfrey, and ephedra can be toxic. Since dietary supplements are not tightly regulated, their safety and purity during breastfeeding are often unclear, posing potential risks to both mother and infant.
Always consult your healthcare provider before taking any herbal product while breastfeeding. Even natural doesn’t mean safe in this context. Certain herbs marketed for weight loss, energy, or mood enhancement may contain ingredients that interfere with lactation or infant development. When in doubt, err on the side of caution and rely on evidence-based information from medical professionals.