International programs for combating food insecurity including the recent FAO “How to Feed the World in 2050: High-level Expert Forum” promote agricultural intensification among the main solutions to global hunger. We argue here that hunting and gathering on land and at sea will often result in less food insecurity than farming. In southwestern Madagascar, questionnaire data find farmers more food insecure than neighboring forest foragers and marine foragers. Production data show that farmers produce a greater quantity of food energy, but foragers sell their goods for higher prices resulting in comparable market-valued incomes among all three subsistence modes. A stochastic model finds farming portfolios an order of magnitude more risky (lower z-scores) than foraging portfolios, except when foraging portfolios have low means. This is because farmers experience only three to five harvests per year while foragers may experience 365 harvests. As farmers await future harvests of uncertain quantity, they are more likely than foragers to depend on formal and informal credit. The stochastic model shows that diversification, mixing foraging with farming, can only reduce the risks of farming under limited conditions. We conclude that pressuring foragers to become farmers will increase rather than diminish regional food insecurity.