There are 249 calories in a 3.5 oz serving of Ground beef Ground Beef, crumbled, cooked, drained, rinsed. Calorie breakdown: 57% fat, 0% carbs, 43% protein.here are 249 calories in a 3.5 oz serving of Ground beef Ground Beef, crumbled, cooked, drained, rinsed. Calorie breakdown: 57% fat, 0% carbs, 43% protein.
Sunlight and Vitamin D Synthesis. Exposure to the sunâs ultraviolet (UV) rays is required for vitamin D3 (cholecalciferol) to be produced. Vitamin D3 is synthesized in the skin once your unprotected skin receives exposure to sunlights UV rays. The sun emits three different types of radiation, UVA, UVB and UVC. The ozone layer is good at blocking all of the UVC radiation and most of the UVB, however, none of the UVA radiation.
Human skin can make large amounts of vitamin D when lots of skin is exposed and the sun is high in the sky. Your body is designed to get the vitamin D it needs by producing it when your bare skin is exposed to sunlight. The part of the sunâs rays that is important is ultraviolet B (UVB).