Quick Answer. The effects of caffeine start within 10 minutes after it is consumed, according to ScienceDaily. However, caffeine requires 45 minutes to reach its maximum concentration in the blood. Continue Reading.
The heart, blood, and blood vessels are the three structural elements that ... These nutrients enter the bloodstream by passing through the walls of the intestine.he heart, blood, and blood vessels are the three structural elements that ... These nutrients enter the bloodstream by passing through the walls of the intestine.
when the food gets digested it goes to small intestine then inside the small intestine there is the villi these absorb the nutrients(carbohydrates,proteins,fats) and then sent â¦ to the blood stream (circulatory system) and in the large intestine the water is absorb and sent to the blood stream.he energy is used by the entire body. The heart also uses it to pump blood around the body. This is the connection between the digestive and circulatory system. The small intestine contains many blood vessels which absorb the nutrients from the food into the blood.