Final answer:
Phytochemicals are compounds in plants that may be necessary for good health. They can act as antioxidants, regulate enzyme activity, impact gene expression, and have psychotropic effects. Individual metabolism can vary, impacting the safety and effectiveness of these compounds.
Step-by-step explanation:
Phytochemicals are naturally occurring compounds found in plants, that are not yet classified as nutrients but may be necessary for maintaining good health. They are involved in a plant's defense mechanism against diseases and pests, and they also contribute to the plant's colors and flavors. Some of the physiological effects in humans include:
- Acting as antioxidants to combat free radicals, which may reduce the risk of cancer.
- Regulating water and enzyme activity, which is vital for various bodily functions.
- Affecting root permeability and chlorophyll formation, which indirectly influence nutrient absorption and metabolism.
- Influencing the metabolism of proteins, amino acids, vitamins, and oils.
- Having mitogenic effects, which involve the activation of enzymes involved in cell replication.
- Influencing transcription factors, which can increase or decrease gene expression, potentially affecting overall health and susceptibility to diseases.
- Some phytochemicals are also known for their psychotropic effects in humans, as seen with compounds like nicotine and morphine derived from plants.
However, individuals can vary significantly in their capacity to metabolize these compounds, which can impact the efficacy and safety of phytochemicals in the diet. Digestive health, particularly the action of gut microflora on plant fibers, can lead to the production of biologically active compounds that augment human metabolism and may prevent or ameliorate conditions such as coronary heart disease (CHD) and type II diabetes.