The loss of ability to absorb vitamin B 12 (B 12) is the most common cause of adult B 12 deficiency. Impaired absorption of vitamin B 12 may be due to a loss of intrinsic factor or to a number of other conditions that decrease production of gastric acid, which also plays a part in the absorption of B 12 from foods.
One of the best natural insect repellent is Lemon Balm. If you insist to go for organic route, Lemon Balm which contains high Citronellal contents is able to repel insects such as mosquitoes, flies, ants and etc. However, Lemon Balm does not deter butterflies or bees.
Lemon Eucalyptus Oil. Repel Lemon Eucalyptus Repellent provided 120.1 minutes of mosquito protection, more than a repellent with a low concentration of the chemical DEET (Off Skintastic for Kids with 4.75% DEET provided 88.4 minutes of protection) and less than Off Deep Woods with 23.8% DEET, which provided 301.5 minutes of protection.