Abstract
In the human life cycle the period of highest susceptibility to hazards is before and around conception. A long historical record shows that an inadequate maternal diet, including a deficiency of single nutrients, depresses sex hormone levels, which reduces the rate of ovulatory maturation, delays ovulation and slows down embryonic growth producing smaller babies and defects in children. A slow-down in ovulatory maturation can also cause damage to the genome or mutations including chromosomal aberrations. Many toxic substances also cause mutations. Some essential nutrients and many substances in food, such as chlorophyll, not classified as ‘essential’, are nevertheless antimutagens. A modest-but-adequate standard of nutrition for women of reproductive age is summarized.