Fenugreek - one of the best and strongest herbs for increasing milk production. When taken in very large amounts, Fenugreek is also used for lowering blood sugar levels, and is, therefore, not recommended for use by diabetics or those who are on strict insulin regimens to regulate their blood sugar levels. Other Herbal Treatments that have been used to increase milk supply are: alfalfa. spirulina. goat's rue. raspberry leaf. fennel. brewer's yeast. stinging nettle. shatavari.