Low intake of selenium and zinc during pregnancy increases the risk of congenital heart defects

Congenital heart defects are the most common birth defect on a global scale. The condition is associated with a number of different complications and even comes with an increased risk of infant death. Maternal nutritional status is vital for the development of the fetus, and a team of Chinese scientists has looked closer at how selenium, zinc, and copper affect the development of the disease. They found that a relatively high intake of selenium and zinc lowers the risk of congenital heart defects. Therefore, the scientists call for increased focus on these two minerals during pregnancy and advocate the use of supplements.

Congenital heart defects occur during the early stage of pregnancy when the heart of the unborn child develops. The condition is a result of different deformities of the heart or coronary arteries. In many cases, these heart defects are not discovered until years later. The symptoms depend on the individual deformity and the age of the child. The most common symptoms include difficulty with latching on and sucking, rapid breathing, slow weight gain, a blue tinge to the skin and lips (cyanosis), sweating, heart murmur, and heart failure. Congenital heart failure can be treated with surgery, medicine, artificial heart valves, or pacemakers.
Worldwide, nine out of one thousand babies are born with congenital heart failure and it is the most common cause of death as a result of congenital deformities.
There can be different underlying factors such as hereditary factors (e.g., Down’s syndrome), virus infections (e.g., measles), medical drugs, large alcohol consumption during pregnancy, and chronic diseases in the mother such as diabetes. It appears that the diet’s nutrient content also plays a role and that deficiencies may have serious consequences.

Scientists: More focus on selenium’s and zinc’s role in preventing congenial heart defects

It’s commonly known that selenium, zinc, and copper are important for fertility, cellular construction, gene activities, and fetal development. The nutrients are also an element of some powerful antioxidants that protect cells and tissues against oxidative stress caused by free radicals.
Animal studies have demonstrated that zinc deficiency during pregnancy may lead to heart deformities in the offspring. Too little selenium can trigger a miscarriage, premature delivery, low birth weight, and ruptured fetal membrane. A copper deficiency may cause heart deformities (in rats), while excess copper may cause fetal death.
When it comes to congenital heart defects in humans, the role of selenium, zinc, and copper remains unclear, however. Therefore, a team of Chinese scientists wanted to study this closer. They collected hospital information about 474 children with congenital heart defects and 948 healthy children (control group).
The participants were from the Northwestern part of China, and the scientists looked closely at the expecting mothers and their total intake of selenium and zinc from the diet and from supplements during the first trimester of their pregnancy. In addition, they looked at the relation between zinc and copper and selenium and copper, respectively. The study showed that a relatively high intake of selenium and zinc during pregnancy was linked to a significantly lower risk of congenital heart defects in the babies. This, however, depends on whether the relative copper intake is high or low.
In their conclusion, the scientists call for increased focus on higher selenium and zinc intake during pregnancy from food or supplements, as this appears to be able to lower the number of children born with heart defects. The new study is published in Nutrients.

• An estimated one billion people worldwide are believed to be deficient in selenium
• Zinc deficiencies are also quite common

Lack of selenium and zinc is quite common for many reasons

We get zinc from meat, shellfish, dairy products, nuts, kernels, and beans. Animal sources of zinc have better absorption in the body. Zinc deficiencies are mainly a result of unhealthy eating habits. Other factors that lower your zinc status are high intake of iron and calcium, large alcohol consumption, and the use of diuretics.
Selenium is primarily found in offal, eggs, fish, and shellfish. The selenium content in crops depends on how much selenium is in the soil. Studies show that the farmland in large parts of the world, including China and Europe, is selenium-depleted. This contributes to the widespread selenium deficiency. For decades, farmers have fed extra selenium to their livestock as a way of preventing deficiency symptoms such as poor fertility.

Pregnancy supplements

The Danish health authorities advise women of childbearing age to take extra folic acid, iron, and vitamin D if they plan to become pregnant. There are special pregnancy supplements that also include selenium and zinc. Make sure to buy high-quality supplements that the body can easily absorb and utilize.

References:

Jiaomei Yang et al. Maternal Zinc, Copper, Selenium Intakes during Pregnancy and Congenital Heart Defects. Nutrients 2022

Aparna Shreenath. Selenium Deficiency. StatPearls. May 6, 2019

Jones GD et al. Selenium deficiency risk predicted to increase under future climate change. Proceedings of the National Academy of Sciences 2017