Genetics Aren't The Only Thing That Determine Your Height

You may think that the genes you inherited are solely responsible for your height. After all, tall parents tend to have children who sprout higher than their classmates, and short parents seem to produce children who are always at the front of the line. That's probably happened in your family as well.

It's true that genetics plays a large role in how tall or short you'll wind up as an adult. But genetics is pretty complicated. There is no single gene for height. Height is a characteristic that is determined by polygenic inheritance, which means that multiple genes contribute to how tall you'll be (per National Institutes of Health). For example, genes that indirectly determine height affect the growth plates — areas of new bone made up of cartilage near the ends of long bones in children and teens (per KidsHealth). There are more than 700 known genes — with many more to be identified — that contribute in some way to height.

How large a role does genetics play in determining height? It's estimated that the heritability (i.e., attributed to genetic effects) of height is between 60 and 80 percent, with 20 to 40 percent attributed to environmental effects (per Scientific American). Much of height's heritability depends on ethnicity and gender. Based on a variety of studies, it's 80 percent for white American men, 78 percent for Finnish men, 75 percent for Finnish women, and just 65 percent for Chinese and certain African populations.

Besides genetics, there are other factors that influence height, with childhood nutrition being chief among them. Adequate protein is the most important nutrient needed for a child to achieve his or her highest potential genetic height. Calcium and vitamins A and D also play a part. Childhood malnutrition, perhaps due to low family income or poor education, can have a negative effect on height.

Adult height is reached after puberty. For a girl, it's about two to three years after menstruation begins, generally the mid-teens; for boys, it's commonly during the late teens, although it can happen up to the early 20s (per EverydayHealth). Getting adequate nutrition before puberty starts is essential for a child to reach full height.

In addition to a proper diet, height may be affected by a child's activity level, access to health care, exposure to infectious diseases, and, in some cases, ethnicity, although studies have shown that when families from certain countries move to another with more nutritious food, better healthcare, and more employment opportunities, the height of their children is influenced.

Finally, there are medical conditions that interfere with normal growth, such as congenital disorders that can lead to a shorter or larger stature and hormonal irregularities during childhood that can alter height (per Healthline).

Once you've reached your adult height, there's nothing that can be done to increase it — except for, you guessed it, wearing heels. As for decreasing your height, give it time. A person can lose a total of one to three inches of height starting after age 40.