A new paper from the University of Liverpool has found that frequent consumption of low-calorie sweetened (LCS) beverages may help people to eat less and feel more positive about their eating.

Many people consume LCS beverages, however their effects on appetite and weight remain unclear. In particular, there is concern that LCS beverages may encourage a preference for sweet-tasting foods and thereby promote overeating and weight gain.

However, another possibility is that people who regularly consume LCS beverages are trying to control their food intake and eat less. For example, by consuming them in response to food cravings, LCS beverages might satisfy the desire for sweet taste.

To test this idea, the Liverpool researchers designed an experiment to “induce” chocolate cravings in their participants (who were all regular chocolate eaters). Half of the participants had to unwrap, smell and imagine eating their preferred bar of chocolate, but without being allowed to eat it. The other participants were in the control group – they carried out the same task but with a wooden block.

Participants’ ratings for chocolate craving increased in the chocolate group but did not change in the control group. This confirms that the procedure was successful in making half of the participants crave chocolate.

Next, all participants were given access to plentiful quantities of sweet and savoury snack foods and drinks (including LCS beverages) and told to eat as much as they wanted.

The results showed that calorie intake was higher for participants in the chocolate-craving group compared to the control group, but only for participants who were non-habitual consumers of LCS beverages. For frequent consumers of LCS beverages, there was no difference between the chocolate-craving and control groups.

This suggests that the frequent consumers were somehow protected from craving-induced increases in food consumption, perhaps because they were consuming LCS beverages as a way to satisfy their food cravings.

So to test this, the researchers ran another study using the same chocolate craving inducement. The participants were a new group of frequent LCS beverage consumers and a further twist was added to the experiment. For half of the participants, LCS beverages were available with the snack foods, and for the other half, LCS beverages were not available.

This second study did not replicate the results of the first study – participants in the chocolate-craving group ate more than participants in the control group, regardless of whether LCS beverages were available or unavailable. Overall, these results indicate that LCS beverages did not consistently protect consumers against craving-induced increases in food intake.

But, there were some other interesting findings – overall, calorie intake was lower when LCS beverages were available (compared to when they were unavailable). Participants also felt less guilty, more in control of their eating and reported greater meal enjoyment when LCS beverages were available (vs. unavailable).

These findings add to the ongoing debate about the effects of LCS beverages on appetite control and weight management. Overall the study suggests that LCS beverages may help some people to eat less and also feel more in control and less guilty about their eating. So, in addition to their role in managing food intake, these beverages could also fulfil an important psychological function.

Link in the full paper: Niamh G. Maloney, Paul Christiansen, Joanne A. Harrold, Jason C. G. Halford, Charlotte A. Hardman. Do low-calorie sweetened beverages help to control food cravings? Two experimental studies. Physiology & Behavior 208 (2019) 112500, https://www.sciencedirect.com/science/article/pii/S0031938418310199?dgcid=coauthor