Date: May 7th, 2009

Seminar Title: "Effects of sucrose on nutrient intake, satiety and mood"

Speaker's Name and Affiliation:

• Marie Reid
• Queen Margaret University, Edinburgh, Scotland

Presiding Chair: Harry R. Kissileff, Ph.D.

Rapporteur: Kathleen L. Keller, Ph.D.

Attendees and their Affiliation:

Kathleen Keller	Columbia/Obesity Research Center
Harry Kissileff	Obesity Research Center
Gerry Smith	Weill Medical College
Timothy Walsh	NYSPI
Susan Carnell	Obesity Research Center
Sally Lederman	IHN
Tony Sclafani	Brooklyn College
Allan Geliebter	Columbia/ Obesity Research Center
JA Grinker	University of Michigan

Summary: (Prepared by the speaker)

Simple carbohydrates might adversely affect appetite and mood by various hypothetical physiological mechanisms, but studies need to control psychological factors influencing mood, eating patterns, satiety and craving, by blind administration and maximizing ecological validity. When subjects are aware, or can infer, that they are consuming sucrose, then changes may be due to cognitive expectancy effects. When eating is highly experimentally controlled, experimental demand characteristics may affect nutrient intake. In three longterm studies lasting 5 weeks, normal weight, overweight and obese women all partially compensated for sucrose added blind to the diet in carbonated soft drinks (compared to aspartame-sweetened controls) by reducing free energy intake, although not to the full energy value of the supplement. Compensation varied depending upon their free diets; it is easier to 'hide' added energy in a diet that involves high energy intake and high daily variation. There was also weight gain and loss in different participants over the course of the study, but no systematic effect of added sucrose. Such variations need to be considered in interpreting research findings. Under blind conditions cognitive factors do not affect satiety, appetite, or mood after sucrose. It was not possible to influence diet or mood by labeling drinks as 'sugary' or 'diet'. However, people's cognitions about study participation still influenced their food choices. Difficulties of dietary regulation (such as obesity) may involve cognitive expectancy effects over-riding physiological satiety mechanisms. Sucrose does not appear specifically to impair physiological satiety mechanisms, even in overweight or obese women.

Discussion:

Q1. When you refer to ¡°sweet liquids¡± being less satiating, are you also referring to diet drinks?
A. Yes, we also use artificially sweetened drinks in our studies.

Q2. Could you explain the arrow from the ¡°reporting/rating¡± to ¡°mood?¡±
A. The act of actually making a rating can impact on one¡¯s mood.

Q3. My sense is that the physiological steps would be both early on in the eating process, but also later. By that, learning about food/eating would then influence your appraisal of the food the next time that you come across it.
A. Yes, that is true.

Q4. What was your answer to the question under artificial sweeteners?
A. Whether it is appropriate to use them given the new research that suggests they have effects on the body in their own right.

Q5. Do most people detect the difference between artificial sweetener and sugar?
A. Most people cannot detect the difference. We use a drink called Iron Bru (made in the UK) which has a pretty good diet version.

Q6. What artificial sweetener is used in the drink?
A. Not sure, but I think it¡¯s saccharin.

Q7. Comment: The reason that I ask is because there were two recent studies that suggest that saccharin and sucralose lead to differential brain activation, so these sweeteners might be processed differently.
A. I wasn¡¯t aware of those studies, but that is very interesting.

Q8. Typically, there are two ways to assess the effects of a supplement in a diet. You can add the supplement to the diet, or place the supplements in foods. Do you think this can effect the outcomes of the study?
A. I think that most of these studies were done by giving the supplement separately, so I am not sure.

Q9. What are the adverse effects you are referring to with respect to sugar consumption.
A. Mainly adverse effects on mood.

Q10. You aren¡¯t talking about people eating sugar by itself, right?
A. No, we are looking at sugar-containing foods.

Q11. You said that drinks were given between meals. Are you aware of David Booth¡¯s hypothesis that people do not compensate for calories consumed between meals?
A. Yes, in our short-term meal, we gave them as a meal and we saw similar effects as to when they were given between meals. Thus, we opted to have subjects consume the drinks between meals.

Q12. Do you think that giving these extra calories in a different form would have had a different effect?
A. That would have been interesting to look at.

Q13. Is the portion size for the Iron Bru drink the standard portion size? The size you have shown (6 oz) is smaller than our typical portion size.
A. These smaller sizes are standard in Scotland.

Q14. Were your subjects allowed to drink other beverages or drinks during the study?
A. We didn¡¯t restrict our other beverage consumption, but they had to like carbonated beverages in order to be enrolled in the study.

Q15. For the mood diaries that subjects kept throughout the study, did you have any way to ensure that they filled them out in a timely manner (and not all at once?)
A. That is an issue that all free living studies are faced with. We gave the subjects random calls and also reimbursed them so they would take the study seriously. But, we cannot be sure.

Q16. Comment: You might want to look into a computerized method of keeping these diaries. I believe that De Castro has been using these procedures and they time stamp when subjects enter data.
A. Yes, that is a good idea.

Q17. I¡¯m not following why when the subjects expected sugar, you expected lower compensation from them.
A. We were looking at literature that sugar promotes higher intake of carbohydrates, so I guess we were thinking about it from that direction.

Q18. Was this drink supplement (Iron Bru) universally liked in your study?
A. Yes, before we let subjects into the study, we gave them a preference test to ensure that they liked the beverage.

Q19. What flavor?
A. It tastes more like an energy drink than anything. Not really a specific flavor.

Q20. Do you add any thickeners to the diet version to mask the texture effects from sucrose?
A. I don¡¯t think so.

Q21. If would be useful to know how much of the compensation is from the drink vs. from the diet.
A. Yes, I don¡¯t have those data.

Q22. How did you recruit the obese subjects?
A. We recruited around the university, but we informed subjects that it was not a weight loss study (although we think that some of the obese subjects may have used this period to focus on weight loss).

Q23. Was the reduction in total fat intake significant across the study?
A. Yes

Q24. Did you ask them to guess what version of the drink (sugar-sweetened or artificially sweetened), and if they got this right, did it effect their outcomes?
A. That would be interesting, but we haven¡¯t done that.

Q25. Did you find any differences in anxiety over the course of the study?
A. No.

Q26. Did you find any effects on hunger and satiety?
A. No, we didn¡¯t.