 Wow. In general, it is more difficult. Thanks Barbara for the introduction. Also, thanks to the organizer to give the physiologists to Hayam to talk about the impact of yogurt on appetite control, energy intake, body composition. In general, in physiology, when we address an issue, we are seeking explanations in order to ultimately better intervene. So I will also do that today by trying to answer the following question. Is it possible that yogurt might be a facilitator of appetite control? If yes, why? I have not prepared a disclosure slide. You would have read that I received grants from Nestle, why they're reformers of Canada. They're a research institute in the U.S. And I would have also told you that I have a particular sympathy for this research field. My father was a cheese maker. So the study of the effects of dairy is to some extent dear in my heart. So is it possible that yogurt can modify appetite control? If yes, why? Let's start with the most simple answer, a replacement effect. A displacement effect of less healthy food, according to which an effect of yogurt consumption might promote benefits just via the reduction of the consumption of sweetened beverage as it was shown by this group, Skinner et al. some years ago in children. So we might reasonably argue that if there is a regular yogurt consumption, there might be less energy than food, less i-fat foods. And then, by the way, a facilitation due to the reduced consumption of less desirable foods. This has been also examined recently in a more standardized context, the laboratory context, by French investigators who compared yogurt to chocolate bar containing more fat, more sugar, and calorie for calorie as a preload. Yogurt was a promoter of a facilitation of appetite control. Lower hunger sensations, desire to eat, greater fullness. But there was no difference in the time to request the following dinner and also no difference in subsequent energy intake. Of course, we wish to modify appetite sensation, but we ultimately also wish to change energy intake with the dream to have some impact on energy, on body weight, and composition. Second explanations, the most obvious one. As indicated by Dr. Fisberg, there are good nutrients in yogurt and some nutrients which have been specifically associated with the control of energy intake. This is the case of calcium, and I like referring to a concept that was introduced by Michael Tordoff some years ago when he described the hypothesis of a calcium-specific appetite control. So this was derived in animals, and one of the key arguments is that calcium deficiency favors a preferential calcium intake when the opportunity is given. So our interpretation might be that if such a calcium-specific control exists, it might be a defense mechanism to protect homeostasis against the side effects resulting from not enough calcium in the diet and not enough to exert the regulatory role of the mineral. So of course, the next question is, is it possible to see some indication in humans about a calcium-specific appetite control? So we tried to do that some years ago in a preliminary study, a small clinical trial in which we specifically recruited very low calcium consumers, not necessarily diagnosed deficient individuals, but our criteria is, in this case, less than 600 milligrams per day. And they were subjected to a 15-week weight-reducing program being supervised by a dietitian, giving the same guidelines to the control subjects receiving a placebo versus those receiving a calcium plus vitamin D supplementation. You see that the outcome on body weight was not the same. In fact, if we compare pre- and post-values in this case, this decrease of one kilo of body weight was not statistically significant by itself, which might lead some people to say that our dietitian was not brilliant in this case. In fact, she was thus doing the same for the two conditions and weight loss as well as fat loss was greater in supplemented individuals. And when we were using a buffet-type meal to measure ad libidum energy intake before and after the protocol, you see, for instance, that spontaneous ad libidum lipid intake was increased in the control group and decreased in the supplemented group, a significant difference between the two trends, and maybe reinforcing the idea that even in these subjects, calcium need may be a driver for modulated appetite control. Proteins are also a player. We like saying in physiology that proteins is the category of macronutriene that has the greatest thermogenic activity, and also that has a more pronounced impact on the control of energy intake. An example in this case is a study performed in Toronto in the lab of Dr. Harvey Anderson using a preload that consisted of either water or water plus whey protein with this amount of protein in each condition. I focus on the cumulative energy intake. I mean here the ad libidum energy intake during the buffet-type meal which followed the preload, plus the calorie content of the preload, and in each case, there was a full compensation with a particularly pronounced reduction in total energy intake after the 40-gram whey protein preload supplementation. Let's talk about yogurt. To some extent, this was reexamined recently by Douglas and Colleague who use a Greek yogurt snack as a preload with different protein contents and the control was a no-snack situation according to other studies. This high protein yogurt reduced hunger, increased fullness, and delayed subsequent eating. So the time to request the subsequent meal was longer for the high protein diet. So satiety was prolonged in this case. But the 600-kcal snack content was not fully compensated despite a lower subsequent energy intake at dinner time. I would be tempted to say if the delay had been standardized, ultimately we might even have seen a difference in energy intake. Also, some biomarkers fitting with the global story, do we see some hormonal adaptations that are concordant with an impact of yogurt, of their rate on appetite sensation? Just one example, again from a Canadian study that was recently reported. Again, it is important to emphasize that low-calcium consumers were recruited and subjected to a two-week diet restriction program and a subgroup received a low-dairy treatment and the other group, a high-dairy. The concordant hormonal change was pertaining to PYY, which is an hormone known to produce reducing effect on energy intake. Under the high-dairy condition, there was an increase in the peptide when tested in a meal test. So during four hours during the meal test and you see the change when there was the low-dairy condition. On the left, the total area under the curve indicating that the high-dairy increased the concentration of the peptide and the opposite for the low-dairy condition. Dr. Fisberg referred to the food matrix of yogurt. It is indeed a flexible food having the possibility to be modified to have a modification on the structures independently of the nutrient content. An example that used this strategy in a mixed manner. So the Luke Cattel study, the authors enrich yogurt with fiber and it was also here a study of supplementation of nutrients since they added proteins to the mixture which promoted a decrease in subjective appetite as well as a decrease in subsequent energy intake. I show you results of a work that is not yet published. We also try to cook, to do some food design in order to strictly perform some modification of the structure of yogurt without having a change in the nutrient content of the food. So the target was isocaloric, isoproteinemic, isovolumetric yogurt formulation to see if a strict change in the food matrix might per se influence spontaneous food intake. So in this case our preload of yogurt was given two hours before the buffet type meal. So we had a schedule with a clinical mind. We were saying in the real life of people who might be hungry between a breakfast and a lunch time the snack would be welcome here and it is then a more realistic way to test the compound under free-living conditions. We had five conditions to which were submitted every subject. So the control was yogurt tree with a ratio of cazine on whey protein of 2.8 on 1. You have the reference here in milk and we were able to modify the composition to have a ratio of 1.5 to 1. So we were increasing the ratio of the rapidly available protein that is whey protein while keeping the same amount of protein and the other formulations were formulations with an addition of fibers. So I draw your attention on two results. The comparison of yogurt one with a high ratio of whey compared to the control, a substantial decrease in energy intake at lunch time during the buffet type meal. We also had this trend with yogurt four and the particularity in this case is that it was more appreciated, perceived as more palatable with increased hunger feelings but despite that a lower energy intake. We will certainly pursue the evaluation of this type of formulation. So just to make brief calculation about the compensation we had that 10 o'clock yogurt of 60 calories that was inducing a decrease in subsequent energy intake of almost 200. So that was a step towards the good direction. The final explanation again according to the first talk of this symposium yogurt can be the vector of microorganism. In the field of obesity we become sensibilized to the issue of gut microbiota and the group of Jeff Gordon was particularly good to emphasize some differences in the bacteria profile of obese individuals versus lean individuals. So in animals as well as in humans we have indications of a greater relative abundance of firmicutase compared to another major category of bacteria the bacteroidatase. And recently we tackled this issue by benefitting of a formulation combining a lactobacillus rhamnosis CG with a small amount of prebiotics to increase the viability of the bacteria. And we tested this formulation in this case it was peel but it could be easy to incorporate the probiotics in the yogurt. So you see in women over 12 weeks always with the protocol of the dietetic supervision guidelines aiming at a specific energy deficit with loss, fat loss were greater in the supplemented group compared to the placebo group and the physiologist calculated the energy equivalent of delta fat and delta lean body mass to reach the conclusion that the estimated body energy deficit was about 50% greater under these conditions in supplemented women. So just a few words before concluding about weight variations. Do we have some indications that yogurt might influence per se body weight stability and could be used in the context of body weight management? Let's start with maybe the oldest study that was published some years ago by Professor Michael Zemel who told me that he had the data much before the publication but he waited and waited because he didn't know exactly what to tell about the finding of a reduction of almost 5 kilos of body fat mass over a year in African-American subjects taking a yogurt per day. So that was the first indication and recently it received the support of population data. It is small. This is not because I do not wish that you see the data. I borrowed directly this table from the paper of the group of Dr. Paul Jakes. In Quebecois we prefer saying Paul Jacques and briefly they measured over time body weight change in individuals reporting and let's say a significant consumption I am seeking three servings per week so we talk about almost regular consumers being compared to almost non-consumers and you should see here if you have good highs that weight gain over time was lower in regular yogurt consumers. And the last slide of results the last one but not the least the very interesting work of Mosaferian et al. who recently reported body weight changes over four years in a large number of people when analyzing data on a per food group basis to conclude that there are nuts but also among the champions of body weight stability is yogurt compared to many other foods. So is it possible that yogurt can facilitate appetite control? Yes, maybe via the replacement of less healthy foods by providing essential nutrients and also because of the flexible food matrix that give possibility to those being interested by functional foods. The last slide and not the least from the physiologist clearly we tend to describe yogurt as a healthy food having potential benefits on energy balance and you see the list of factors that I investigated over the last year which are all associated with the proneness to be in positive energy balance. High fat, high density diets, sedentaryness, short sleep duration, demanding cognitive work on healthy behaviors, chemical pollution, weight cycling. So clearly we are living in an obesogenic world and even if we have good results with yogurt please do not present yogurt as a magic pill to take and charge the obesity epidemic. That's it. Thanks for your attention.