New research published in The BMJ this week describes a link between elevated potato intake before pregnancy and an increased risk of gestational diabetes.
The humble potato truly is a global product. From basic beginnings in South America, the starchy, tuberous crop has taken the world by storm.
Europe, the Americas and the countries of the former Soviet Union were once the only major consumers of the basic spud; recently, markets in Asia, Africa and Latin America have dramatically increased their taste for the potato.
In 2013, an estimated 368 million metric tons of potatoes were grown. Today, China is the largest producer, accounting for around one third of the total potatoes grown on planet earth.
The popularity of the potato is easy to understand: they are a hardy, nutritious crop and thrive in many climates. They also contain a wealth of caloric fuel and a smorgasbord of healthy compounds, including high levels of vitamin C and B6, thiamin, folate, niacin, riboflavin, magnesium, iron, phosphorus and zinc.
However, there is no such thing as a free lunch. A new study finds a link between a dietary increase in potatoes and a heightened risk of gestational diabetes.
Potatoes and pregnancy
Globally, potatoes are the third most consumed crop, after rice and wheat. In the US, 35% of women of reproductive age eat potatoes on a daily basis. Any food item this prevalent is worthy of further investigation.
The Dietary Guidelines for Americans still includes potatoes in the vegetable group (the UK includes them in the “starchy food” group) and promotes their consumption.
Researchers from the Eunice Kennedy Shriver National Institute of Child Health and Human Development in Rockville, MD, in conjunction with Harvard University in Boston, MA, decided to study the vegetable’s ramifications on pregnancy. The team followed more than 21,693 singleton pregnancies over a 10-year period.
The data was taken from the Nurses’ Health Study II (1991-2001). Participants had no previous gestational diabetes mellitus or chronic diseases. Diets were assessed with questionnaires every 4 years. Of the pregnancies, 854 were affected by gestational diabetes.
Even after controlling for factors including age, family history, diet quality in general, BMI and family history of diabetes, higher potato consumption before pregnancy was linked to an increased risk of gestational diabetes.
Gestational diabetes is a major concern. Not only is it associated with negative perinatal outcomes, it also raises long-term cardiometabolic risks for the mother and child.
Although the researchers are quick to acknowledge that the study was observational and therefore cause and effect can not be drawn, the results, perhaps, should not be such a surprise.
Previous studies into the negative aspects of the potato
Previous studies have shown that, although the potato does have a great deal going for it, not all that glitters is gold. Unlike other vegetables, potatoes contain a large quantity of starch.
This starch is readily and quickly absorbed by the body, giving the potatoes a high glycemic index. Consequently, a meal high in potatoes can induce a spike of glucose in the blood. This spike can cause oxidative stress to pancreatic beta cells and potentially exhaust them over time.
Potatoes have previously been found to increase concentrations of fasting plasma glucose, insulin resistance and the risk of type 2 diabetes.
Added to the chemistry of the raw potato, the method in which it is cooked can also have an impact on health. According to the paper, French fries, for instance, contain extra gremlins: “degradation products from the frying oil and dietary advanced glycation end products that are generated during the frying process.”
These types of products have previously been shown to increase the risk of insulinresistance and diabetes. The present study’s authors conclude their report with some simple advice to minimize the potential risks:
“Higher levels of potato consumption before pregnancy are associated with greater risk of gestational diabetes mellitus, and substitution of potatoes with other vegetables, legumes, or whole grain foods might lower the risk.”
The team hopes that further down the line, government and other official dietary standards might be changed to reflect the new evidence that is mounting against the potato.
Medical News Today recently covered research showing that maternal gestational diabetes might be linked to autism in the offspring.
Written by Tim Newman