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.
The organ that absorbs nutrients during digestion is the small  intestine. The walls of the small intestines will absorb digested  nutrients into the blood stream.he blood carries nutrients from the small intestine to all over the body. The villi in the small intestine allow nutrients from digested food to pass through the intestinal w â¦ all to the blood vessels. Then the blood carries the nutrients away. 1 person found this useful.