HUMAWORM is based on blood volume levels. The human blood volume amount is about 1/11th of body weight with most all adults having about 5 quarts (4.7 liters) of blood. This is why HUMAWORM will work equally as well for 100 pound adults as it will for 250 pound adults. When a person is over 300 pounds, we SOMETIMES recommend that 6 capsules per day instead of the usual 4 are taken.