Our tests and research have shown the best mattresses for heavy people are firm and supportive. As a general rule-of-thumb, the heavier a person is, the firmer their mattress should be. A mattress that feels too soft may sink excessively and cause issues like lower back pain and pressure points along the spine. Mattresses with supportive materials like latex, high-density foam, and zoned coils can be particularly beneficial for heavier individuals.