Poor diet has a clear impact on human health, and what nourishes people as children, and even in the womb, can affect them in later life. New research suggests that lack of oxygen in the womb, combined with high salt intake in later life, can lead to vascular problems.

[salt]Share on Pinterest
Excessive salt intake combined with hypoxia before birth can cause cardiovascular problems.

Findings from the research, carried out by PhD student Sarah Walton, are published in The Journal of Physiology.

Oxygen plays a key role in fetal development, especially in the second and third trimester. Hypoxia, or lack of oxygen, can lead to Intrauterine Growth Restriction (IUGR), which may cause problems before and at birth, such as low birth weight and premature delivery.

Later in life, the impact of IUGR has been linked to problems as varied as cerebral palsy, cardiovascular dysfunction, kidney problems and even attention-deficit hyperactivity disorder (ADHD).

Reduced oxygen supply to the developing fetus is a common pregnancy complication in humans. It may be caused by smoking or severe sleep apnea.

Other risk factors include living in a high-altitude environment, preeclampsia, pre-existing cardiovascular disease in the mother – such as cyanotic heart disease, heart failure or pulmonary hypertension – or twins in the womb.

Fast facts about salt
  • One slice of white bread contains 80-230 mg salt
  • A 4-oz slice of restaurant pizza, cheese with plain crust contains 510-760 mg
  • One restaurant cheeseburger contains 710-1,690 mg.

Learn more about salt

Excessive salt is known to cause cardiovascular disease. Sodium causes the body to retain fluid, which puts pressure on the heart and blood vessels.

The arteries compensate by developing stronger and thicker walls, which ultimately limit the flow of the blood. It can lead to stroke or heart failure.

Too much salt can also lead to kidney disease, as the extra sodium destroys the delicate balance needed to be able to remove excess water from the bloodstream. Higher blood pressure further puts strain on the kidneys, particularly if diuretics are used to help remove extra fluid.

In the current study, scientists used mice whose fetal experience had been complicated by reduced oxygen supply.

The mice were fed either a normal rodent diet or a diet containing high levels of salt throughout adult life.

The team, led by Associate Professor Karen Moritz of The University of Queensland, Australia, evaluated the functional and mechanical characteristics of the blood vessels to investigate the combined impact of lack of oxygen in the womb and a postnatal diet high in salt.

Mice whose mothers had experienced reduced oxygen during pregnancy exhibited growth restriction and increased vulnerability to poor blood vessel function as adults. Given a high-salt diet, they also developed blood vessels with impaired function – a condition associated with stroke and heart attack.

They exhibited degenerative changes in the walls of the aorta and a marked stiffness of the small blood vessels – a risk factor for high blood pressure and a predictor for future cardiovascular events.

Prof. Moritz explains:

High dietary salt intake is endemic in Western societies, largely due to our consumption of processed foods. As such, we may be inadvertently enhancing certain predispositions to vascular dysfunction and stiffness by making poor dietary choices.

Our findings are promising, as consuming a healthy diet may prevent or at least limit adverse cardiovascular outcomes associated with unavoidable complications during pregnancy (such as low oxygen).”

According to the Centers for Disease Control and Prevention (CDC), high sodium intake is a major problem across the US.

The average American adult eats more than 3,300 mg of sodium a day, more than double the recommended limit for most adults.

The 2010 Dietary Guidelines for Americans recommend reducing sodium intake to less than 2,300 mg per day. People aged 51 and older and those of any age who are African-Americans or who have high blood pressure, diabetes or chronic kidney disease should consume no more than 1,500 mg per day.

Medical News Today recently reported that gradual salt intake can lead to high blood pressure.