There is more to diet than sugar
Chazelas et al. (BMJ 2019, 365, 12408) reported that the intake of sugar, including the sugar in fruit juice, was associated with a higher incidence of cancer. A fundamental question is whether it is meaningful to examine in isolation a single nutritional villain, rather than acknowledging the need for a wide ranging, varied and balanced diet?
Fruit juice is a valuable source of bioactive molecules with health-related anti-inflammatory and anti-oxidant properties. For example, a meta-analysis of 22 studies found that a high intake of flavonoids reduced all-case mortality (relative risk 0.74; Am J. Epidemiol, 2017, 185, 1304-1316.). Since 2003 the World Health Organization has recommended the consumption of fruit and vegetables to improve health; however, as intact and juiced fruit have a similar molecular composition it would be predicted that fruit juice would have health giving properties. The most extensive meta-analysis of the benefits of fruit and vegetable consumption found that the consumption of 100% fruit juice (not extrinsically sweetened) reduced all-cause mortality (RR 0.76 ) and specially the incidence of coronary heart disease (RR 0.79) and ischaemic stroke (RR 0.65) (Int J Epidemiol 2017, 46, 1029-1056).
Although Chazelas considered only sugar, diet is too complex a topic to consider one form of one nutrient. The Burden of Disease study found that disease was more likely to be associated with diets high in sodium, low in fruit and vegetables, and low in whole grain, nuts and seeds. An interesting observation was that “A policy focus on the sugar and fat components of diets might have a comparatively smaller effect than that of promotion of increased uptake of vegetables, fruits, whole grains, nuts and seeds” (Lancet 2016, 388, 1659-1724).
An unintended consequence of examining only one nutrient is that it promotes the myth of good and bad foods, when we must emphasize the range and balance of the many foods that will make up a healthy diet.
David Benton, DSc and Hayley A Young, PhD
Swansea University, Wales, United Kingdom.
Competing interests: No competing interests