Fish oil is beneficial to health because it contains omega-3 fatty acids which decrease the risk of heart and blood vessel disease by lowering levels of triglyceride in the blood and slowing up liver triglyceride synthesis. However, human metabolism cannot generate them from other fatty acids in the body making it very essential to be included in the diet. 900 mg of omega-3 fatty acids from fish or fish supplements is the ideal requirement for adults.
On the other hand, there is the downside of fish oil supplement intake.
There is a discrepancy in the levels of omega-3 fatty acids in various fish. Those that are not artificially raised would normally have lesser amounts of omega-3 fatty acids. Aside from that, fish and their products are highly at risk with the contamination of the ocean. In this regard, many studies show fish and fish oil supplements have alarming levels of mercury. Part 2 (Paragraph 2):
The cross-linkage theory provides a good explanation behind the process of aging.
This states that there are additional cross-linkages formed between collagen fibrils as humans age. This contributes to the brittleness of bones, ligaments and tendons which is characteristic of weakened physical activity and change in height and posture as a person grows old. More over, this perfectly describes how cross-linkages formed in skin fibrils results in the decrease in skin elasticity and eventually results to wrinkles.
People age because of the different physical and chemical changes occurring in the body. This can be brought about by the alteration in the levels of certain substances in the body and the formation of reactions between different chemicals. According to the Wear and Tear theory, aging can be delayed by genetically manipulating the protein repair mechanism of our body and the genes that cause aging. Reference: Materials provided.