I can tell you that drinking milkshake during lactation has some effects on your health. First of all, milkshakes usually contain high-sugar and high-fat ingredients, and excessive intake may lead to weight gain and blood sugar fluctuation. This may have a negative impact on your health, especially if you are overweight or have diseases such as diabetes.

Secondly, some ingredients in milkshakes may cause allergic reactions. If you or your baby are allergic to certain foods, such as dairy products or other milkshake ingredients, drinking milkshake may cause allergic symptoms, such as rash, dyspnea or indigestion.

In addition, additives and artificial colors in milkshakes may also have a negative impact on your health. Some people may be sensitive to these chemicals, leading to gastrointestinal discomfort or other adverse reactions.

Finally, the nursing mother's diet should be balanced, diversified and nutritious. Milkshakes can be used as part of the diet, but they should not be the main source of nutrition. Make sure that your diet contains enough protein, carbohydrates, fats, vitamins and minerals to meet the nutritional needs of you and your baby.

To sum up, drinking milkshake during lactation may lead to weight gain, blood sugar fluctuation, allergic reaction and sensitivity to certain chemicals. Therefore, it is recommended to consult a doctor or dietitian before drinking milkshake to ensure a balanced and diversified diet.