Sugar has a direct effect on risk factors for heart disease,
including rising blood pressure, Kiwi researchers have found.
Nutritionists at the University of Otago reviewed all
international studies comparing the effects of higher versus
lower added sugar consumption on blood pressure and lipids
(blood fats or cholesterol), which are important
cardiovascular risk factors.
"Our analysis confirmed that sugars contribute to
cardiovascular risk, independent of the effect of sugars on
body weight," Dr Lisa Te Morenga, research fellow at the
university's Department of Human Nutrition, said.
"Although the effects of sugars on blood pressure and lipids
are relatively modest, our findings support public health
recommendations to reduce added sugar in our diets as one of
the measures which might be expected to reduce the global
burden of cardiovascular diseases."
Dr Te Morenga and Professor Jim Mann studied dietary
intervention trials published in English-speaking journals
between 1965 and 2013, comparing diets where the only
intended differences were the amount of sugars and non-sugar
carbohydrates consumed by the participants, and which
measured the effects of these diets on lipids and blood
Research showed that sugars did not make people more likely
to gain weight on high-sugar diets compared with low-sugar
diets when the total amount of carbohydrates and energy
remains the same.
"However our latest study did find significant effects of
sugars on lipids and blood pressure among these types of
energy-controlled studies. This suggests that our bodies
handle sugar differently to other types of carbohydrates," Dr
Te Morenga said.
"In subgroup analyses we showed that by excluding the trials
funded by the food/sugar industry, we found larger effects of
sugar on lipids and blood pressure."
The release of their findings in the American Journal of
Clinical Nutrition online is timely, she said, as national
and international organisations consider recommendations on
safe dietary sugar intakes.
"Our work provides further evidence to support these
recommendations which have been disputed by the food
industry," she said.
"While there is still a need for further longer term
well-powered studies looking at the effects of sugars on
various health outcomes, it is becoming increasingly
difficult for the food industry to continue to claim that
liberal sugar consumption is risk free."
- Patrice Dougan of APNZ