WO2010115899A1

WO2010115899A1 - Snack food

Info

Publication number: WO2010115899A1
Application number: PCT/EP2010/054543
Authority: WO
Inventors: Rachel Hackett; Penelope Morris; Moira Taylor; Ian Macdonald; Emma Stevenson; Nerys Astbury
Original assignee: Mars Inc
Current assignee: Mars Inc
Priority date: 2009-04-02
Filing date: 2010-04-06
Publication date: 2010-10-14
Anticipated expiration: 2011-10-02
Also published as: GB0905787D0

Abstract

The present invention relates to the use of protein in a snack food for use in weight maintenance in a male human. Specifically, the protein-containing snack food increases satiety which leads to a reduction in the calorie intake at the next meal, resulting in maintenance of weight in a male human.

Description

Snack Food

The present invention also relates to a method of weight maintenance and a dietary regime comprising consuming the snack food between meals.

Generally, it is considered that an adult male requires approximately 2,500 kcal per day in order to maintain his weight. Most usually, this calorie intake is achieved by the consumption of three meals per day.

If the three meals per day account for the total amount of calories required for the male human, the addition of snacks in between meals, (for example, a snack mid- morning between breakfast and lunch and/or a snack mid-afternoon between lunch and evening meal) will increase the daily calorie intake for the male human and result in increasing weight, if the male human's activity level remains the same.

This is a common problem in today's society, particularly in the Western World. This increase in weight can lead to obesity which in turn leads to health problems including diabetes and heart disease.

The simple solution to this problem is to not snack in between meals to bring the calorie consumption during a single day to the required level of approximately 2,500 kcal for a male human. However, due to the long time period (which can be anywhere from 3 to 7 hours) between breakfast and lunch or lunch and dinner, it is often tempting to consume a snack food between meals. However, snack foods often contain relatively high sugar, high fat and are of low nutritional value. These type of snack foods do not provide lasting satiety. This means that no reduction in calorie consumption occurs at the meal following the snack. In fact, the consumption of a high sugar snack leads to a sharp increase in the blood sugar level, followed by a sharp decrease. This decrease can lead to the blood sugar level being below the level at which it was before consumption of the snack. This can lead to a consumption of more calories at the next meal than if no snack had been consumed. The daily calorie intake thus increases, leading to weight gain, unless measures are taken to compensate for the extra calories consumed. To compensate for increased calorie intake, the excess calories should be used, by way of increased activity, usually in the form of exercise. However, many people do not enjoy exercise, or struggle to find the time to fit it into their day.

Therefore, there is a need for a snack food that will prolong satiety until the next meal and therefore result in reducing the calorie intake at the meal, in order to maintain the daily calorie intake at the same level than if the snack had not been consumed between meals.

Therefore, the present invention provides the use of at least 1Og protein in the manufacture of a snack food comprising from 300 to 450 calories (kcal) for use in weight maintenance in a male human. Preferably, the snack food comprises 350 to 420 kcal, most preferably the snack food comprises 390 to 410 kcal, for example, 400 kcal.

It is well established that protein is more satiating per calorie than either carbohydrate or fat but the satiating influence of proteins is variable. The response to a standard protein meal is firstly affected by habitual protein intake. Satiety induced by protein is lower in individuals accustomed to high protein intakes. Whilst the mechanism for this remains to be elucidated, one possibility is that there is an increased number of transporters and therefore more rapid uptake and oxidation of amino acids. Secondly, different protein types vary in their ability to induce feelings of satiety. Animal protein (pork) and vegetable protein (soy) on both satiation and energy expenditure over a 4-day period have been compared. Energy intake was significantly less and subjective feelings of satiety significantly more, with both the pork and soy diet compared to the carbohydrate control, but there was no significant difference between the two. The animal protein diet did however result in significantly greater 24hr-energy expenditure compared to both the vegetable protein diet and the carbohydrate control. Beef, chicken and fish protein have been compared and showed that postprandial satiety was greatest with protein from a fish source.

In an effort to further understanding, egg albumin, peanut protein, gelatin, soy protein, pea protein and wheat gluten have been compared on satiety and subsequent meal intake. It was found that there was no difference in the effect of the six protein types on postprandial satiation or energy expenditure. The use of 60 to 7Og of each protein source however in a group of only 12 subjects may have masked any satiety response to protein type.

A preferred embodiment of the first aspect the protein is whey protein, peanut protein or soy protein. Preferably the protein is whey protein.

The inventors have found that weight maintenance is achieved by reducing the calorie intake at a subsequent meal to compensate for the calorie content of the snack food, which is generally around from 300 to 450 kcal, preferably 350 to 420 kcal, most preferably 390 to 410 kcal, for example, 400 kcal. The calorie intake at a subsequent meal is reduced by approximately the same amount of calories as is contained in the snack food. This effect, surprisingly, is seen in men and not women. The reduction of subsequent calorie intake is determined by the amount of protein in the snack food. The inventors have surprisingly found that the protein has a dosage effect on satiating effect of the snack food and thus the reduction in calorie intake at the subsequent meal. Therefore, preferably the calorie intake at the meal is reduced proportionally to the amount of protein present in the snack food. Preferably, the amount of protein in the snack food is from 10-5Og, more preferably from 20-4Og, most preferably 25 to 35g, for example, 30g.

As a second aspect, the invention provides a method for reducing calorie intake in a male human at a meal comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og protein prior to consuming the meal. Preferably, the snack food is consumed from between 1 minute to 120 minutes prior to the meal, more preferably from 30 to 100 minutes prior to the meal and most preferably from 60 to 90 minutes prior to the meal. The snack food may be preferably consumed 90 minutes prior to the meal.

By weight maintenance it is meant the achievement of a healthy body weight.

For example, this may be the loss of excess weight to a healthy level, and then maintaining the weight at that level. Alternatively, it may mean the increase in body weight for an underweight subject to a healthy level, and then the maintenance of that level. The subject may already be of a healthy weight, and thus weight maintenance in this situation would be maintaining, generally, that weight.

Clearly, weight may fluctuate within reasonable limits and still remain at a healthy level.

Healthy means where no adverse effects on health are seen due to weight (e.g. diabetes due to being overweight, or osteoporosis, muscle wastage due to being underweight).

The increasing amount of protein in the snack food corresponds to a prolonged satiating effect of the snack food, even though the calorie content of the snack food remains the same in all cases. The calorie intake at the meal is always approximately reduced by an amount equivalent to the calorie content of the snack food. However, the amount of calories consumed at the meal reduces, with an increased amount of protein that is present in the snack food. Thus, the invention also provides, as a third aspect a method of weight loss in a male human comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og of protein, prior to consuming a meal. This "dosage effect" of the amount of protein reducing the calorie consumption at the subsequent meal, is unexpected since the amount of calories in the snack food remains the same. Weight loss will occur when the snack food of the present invention is consumed if the male human replaces a snack food comprising 300 to 450 kcal or more that contains negligible amounts of protein for example, a standard chocolate bar or a standard packet of crisps in between meals. This is because these snack foods do not provide a satiating effect and therefore the calorie intake at a subsequent meal will not be reduced. By consuming the snack food of the present invention in between meals, and therefore reducing the calorie intake at a subsequent meal, weight loss will occur in the human male.

A further aspect of the invention also relates to a method of weight maintenance for a male human comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og of protein prior to consuming the meal. The male human's weight is maintained as compared to eating three meals a day and no snacks, since the snack provides a satiating effect resulting in the reduction of calorie content at the next meal equivalent to that of the snack food consumed. This calorie reduction is proportional to the amount of protein present in the snack food, which is in an amount from 10 to 5Og.

A fifth aspect of the invention relates to a snack food comprising from 300 to 450 kcal and at least 1Og of protein for reducing calorie intake at a subsequent meal in a male human. Preferably, the protein is whey protein, peanut protein or soy protein and most preferably the protein is whey protein.

In an embodiment of the fifth aspect the snack food further comprises fibre. Preferably, the fibre is soluble fibre. Surprisingly, the addition of fibre to the snack food further increases the satiating effect resulting in a further reduction of calorie intake at the subsequent meal. Preferably, the calorie intake at the subsequent meal is reduced proportionally to the amount of protein in the snack food. As mentioned previously, the amount of protein in the snack food has a dosage effect on the reduction of calories in the subsequent meal even though the amount of calories remains the same. Preferably the amount of fibre in the snack food is from 8 to 25g, more preferably, from 10 to 2Og, most preferably 12 to 18g, for example, 15g. The snack food may also contain additional nutrients such as vitamins, minerals, fatty acids, amino acids, plant derived micronutrients, including carotenoids, flavanoids, polyphenolic compounds, and others.

The snack food may also comprise flavourings, such as fruit flavourings, sweet or savoury flavourings, sweeteners, yeast extract, vegetable flavourings, vanilla flavouring, chocolate flavourings, or any other suitable flavouring. The snack food may comprise fruit or vegetable pieces, or nuts, seeds and the like.

The snack food may be coated (if solid) with a chocolate or chocolate substitute coating, probiotics, sugar or sugar substitute, syrup, fruit, jelly or any other suitable coating. The snack food may have a filling, such as a fruit, chocolate, sugar or sugar substitute filling or any other suitable filling.

In a further embodiment of the fifth aspect the protein is present in an amount from 10 to 5Og, more preferably 20 to 4Og, most preferably 25 to 35g, for example, 30g. The composition may be liquid, a semi-solid or solid. For example, the snack food may be a snack drink such as a milkshake-type composition. When in a semi-solid format it may be in the form of a mousse or a yoghurt-type snack. When in a solid format it may be in the form of a snack bar, such as a cereal bar, or a nut based bar.

A further aspect of the present invention provides a dietary regime for weight maintenance in a male human comprising a snack food, the snack food comprising from 300 to 450 kcal and at least 1Og of protein between breakfast and lunch and/or lunch and dinner. The dietary regime may comprise the consumption of one snack food to be eaten either between breakfast and lunch, or between lunch and dinner. Alternatively, the dietary regime may include two snack foods, one to be eaten between breakfast and lunch and the other to be eaten between lunch and dinner. By breakfast it is meant the first meal of the day, by lunch it is meant a midday meal and by dinner it is meant an evening meal. The calorie consumption at lunch and dinner respectively will be reduced proportionally to the amount of protein present in the snack food when two snack foods are consumed during the day between breakfast and lunch, and lunch and dinner, respectively. If only one snack food is consumed the calorie intake at the meal directly after eating the snack food i.e. lunch or dinner will be reduced in proportion to the amount of protein present in the snack food. Preferably, the calorie consumption at the meal is reduced by from 300 to 450 kcal.

Preferably, the snack food is consumed from between 1 minute to 120 minutes prior to the next meal i.e. prior to lunch and/or dinner. More preferably the snack food is consumed from 30 to 100 minutes, most preferably the snack food is consumed approximately 90 minutes before the next meal i.e. lunch and/or dinner.

The invention will now be described by way of the following Examples, with reference to the Figures, in which;

Figure 1 shows the energy intake at lunchtime after consuming the snack in the morning for male subjects;

Figure 2 shows the total energy intake throughout the experimental protocol for the male subject;

Figure 3 shows the energy intake at lunchtime for the female subjects after consuming the snack food mid-morning;

Figure 4 shows the total energy intake throughout the experimental protocol for female subjects;

Figure 5 a shows hunger scores throughout the experimental protocol for the male subjects;

Figure 5b shows hunger scores throughout the experimental protocol for female subjects; Figure 6a shows fullness scores throughout the experimental protocol for the male subjects;

Figure 6b shows fullness scores throughout the experimental protocol for the female subjects;

Figure 7a shows the desire-to-eat scores throughout the experimental protocol for the male subjects;

Figure 7b shows the desire-to-eat scores throughout the experimental protocol for the female subjects;

Figure 8a shows the thirst scores throughout the experimental protocol for the male subjects;

Figure 8b shows the thirst scores throughout the experimental protocol for female subjects;

Figure 9a shows the pleasantness of the test meal rated before and after the meal for male subjects;

Figure 9b shows the pleasantness of the test meal rated before and after the meal for female subjects;

Examples

Subjects

Twelve male (mean (±SD) age 25.6 ± 5.6 years, BMI 24.2 ± 1.3 kg/m²) and twelve female (mean (±SD) age 34.0 ± 9.2 years, BMI 21.5 ± 2.3 kg/m²) healthy non-obese subjects were recruited from the students and staff of Queen's Medical Centre, Nottingham, United Kingdom, via poster advertisement. All subjects were non- dieting and non-smokers. Subjects were required to score seven points or less for dietary restraint on the Three Factor Eating Questionnaire [5]. The mean dietary restraint score for the male participants who participated in the study was 3.8 (range 1-7) and the mean score for the female subjects was 3.3 (range 0-6). Subjects were also required to show no signs of depression (score < 10 on the Beck Depression Inventory [6]). No subjects had any food allergies, special dietary requirements or significant current or previous medical history. Potential volunteers were excluded if they consumed > 20% energy intake as protein as previous research has shown that appetite responses to a high-protein test meal vary inversely with habitual protein intake in both male and female subjects [7]. Habitual protein intake was assessed by a 3d food diary which was completed for 2 weekdays and 1 weekend day prior to the start of the study and analysed using Microdiet software. Subjects were also informed of the foods they would be required to eat in the study and were excluded if they disliked any of the test foods used.

Subjective ratings

All appetite and mood ratings were presented using computerised visual analogue scales (VAS). Horizontal line scales were displayed on the monitor with the question presented centrally above the line. The line was end anchored with the terms "not at all" and "extremely" with polarity randomised for each question. A vertical bar appeared in the centre of the line and could be moved into the desired position by the subject using the mouse or the cursor keys on the computer key board. An on-screen button was clicked to confirm each response. All ratings were scored on a scale from 0 (not at all) to 500 (extremely). A set of eleven mood and appetite questions were presented to the subject each time VAS were completed. The questions were in the form of "How (word) do you feel?" where the word was "clear-headed", "desire to eat", "energetic", "friendly", "full", "happy", "hungry", "jittery", "nauseous", "relaxed" and "thirsty". Subjects completed a taste test at the beginning and end of the test meal, being instructed to rate the sensory properties of the test meal (pleasantness, creaminess, saltiness and strength of flavour) using a scale as described for the appetite and mood questions above. Meals and Preloads

Three whey preloads and a water control preload were used in this study. The whey preloads were formulated using commercially available whey protein powder (Instantized Bipro, Davisco Foods, Switzerland), double cream and maltodextrin powder (Cerestar Foods, UK). The exact composition of each preload is shown in Table 1. The protein preloads were isoenergetic (390 to 410 kcal) and contained 12.5%, 25% or 50% energy from whey protein. Each protein preload was made up to a volume of 400ml with water and flavoured with ImI of vanilla flavouring.

Food intake after consumption of the preloads was assessed via ad libitum consumption of a test meal. The test meal consisted of pasta shapes (farfalle pasta shapes, Tesco, UK) which were cooked in a microwave for 13 min in unsalted water and then served in a tomato based pasta sauce (Dolmio express tomato and basil pasta sauce, Masterfoods, UK) with grated cheddar cheese (Tesco, UK) and olive oil (Tesco, UK). The test meal was prepared and served in specific portions sizes (See Table 2) and was designed to provide the same percentage energy from protein, fat and carbohydrate as reported to be the average UK intake in the 2002-2003 National Food Survey. All test meals were freshly prepared on the morning of each trial, chilled in a refrigerator and then re-heated in a microwave when required. The meals were served at 60 - 65°C.

Design

Each subject participated in four trials in a randomized cross-over design. Subjects were instructed to consume a standardised evening meal the night before each trial. The meal was composed to provide 30% of the daily energy requirement for each subject. Each individual's daily energy requirement was calculated using the Schofield Equation [8] to estimate basal metabolic rate and physical activity levels from the International Physical Activity Questionnaire [9]. All evening meals provided 49% energy from carbohydrates, 38% from fat and 14% from protein. These values were based on the average energy intake in the UK reported in the 2002-2003 National Food Survey. The meals were designed to contain foods that the subject reported to eat in their 3d food diary which was completed and analysed before the start of the study.

On the morning of the study, subjects consumed a light breakfast at home between 7.30am and 8am. Breakfast consisted of Rice Krispies (Kellogg's UK) and semi skimmed milk and provided 10% of the individual's daily energy requirement. The subjects were provided with the appropriate amount of cereal and were given a measuring cup marked with the volume of milk to be consumed with the cereal. Subjects were instructed not to eat anything else and only consume water for the remainder of the morning. Subjects arrived at the laboratory at 1 lam and immediately completed the first set of VAS ratings. Subjects were then provided with the preload and asked to consume the entire drink within 5 min. All preloads were presented in a blue plastic beaker with a lid and ingested through a straw, thus masking any visible differences in the appearance of the preloads. Immediately after finishing the preload, mood and appetite ratings were completed and then the subject rested in the laboratory. Further mood and appetite ratings were completed at 30 min and 60 min after the preload. At 90 min, subjects completed another set of VAS questions and were immediately provided with a pre-weighed portion of the pasta test meal. Subjects completed a taste test following one forkful of pasta and were then instructed to "Eat as much as you like". During the first trial, water was provided ad libitum with the test meal however the volume consumed was measured and recorded and the same volume provided in the subsequent three trials.

It was made clear to the subjects by the investigator that they did not have to finish the first portion of pasta but could also have as many portions as they desired. Each portion was weighed in the serving bowl on a balance accurate to O.lg (Sartorius, Germany) before being given to the subject and then the bowl and contents were re- weighed once the subject had finished. When the subject signalled they had finished eating, a taste test and a set of appetite and mood rating was completed immediately. Subjects then remained in the laboratory for a further 60 min and appetite and mood ratings were completed at 30 and 60 min. Statistical Analysis

SPSS software (version 13; SPSS, Chicago) was used for data entry and analysis. All results are expressed as mean values with their standard errors unless otherwise stated. Ad libitum food intake at the test meal was analysed using a two way analysis of variance for repeated measures. Baseline VAS measurements (before the preload was consumed) for each question were compared between trials using analysis of variance (ANOVA) for repeated measures. No significant differences were found between trials therefore repeated measures ANOVA's were carried out on change in VAS score from baseline for all VAS scores collected before the pasta test meal. No statistical analysis has been carried out on the post test meal VAS scores. Significance was set at P < 0.05 for all statistical tests, unless a Bonferroni correction was applied.

Results

Test meal food intake Initially, food intake data were analysed as a complete data set with gender as a factor. There was a significant effect of preload on energy intake (P < 0.001) however, a significant gender by preload interaction was obtained (P < 0.001) therefore all data were analysed separately for males and females.

Male Subjects: Protein content of the preload significantly affected food intake at the test meal (Figure 1). When water was consumed as a preload, subjects ate more compared to the 12.5%, 25% and 50% protein preload trials (P < 0.005). When the 50% protein preload was consumed, energy intake at the test meal was significantly less compared to the 12.5% and 25% protein trials (P < 0.005). No difference in energy intake was observed between the 12.5% preload and the 25% preload trials. A significant linear relationship (R² = 0.93) was found between the protein content of the preload and the energy consumed at lunchtime (P < 0.001). When the energy content of the preload (390 to 410 kcal) was taken into account (Figure 2), there were no differences in total energy intake over the experimental period between trials. Total energy intake in the 50% preload trial was less than in the water trial however this difference did not reach significance (p=0.1). Female Subjects: There were no differences in energy intake at the test meal when female subjects consumed water, a 12.5% or a 25% protein preload (Figure 3). When a 50% protein preload was consumed, female subjects consumed significantly less than when water only was consumed (P < 0.05). Despite no significant differences between the water, 12.5% and 25% preload trials, a significant linear relationship (R² = 0.82) was found between the amount of protein present in the preload and the energy consumed at the test meal (P < 0.05). When the energy content of the preload (390 to 410 kcal) was taken into account (Figure 4), female subjects consumed significantly more energy throughout the experimental period in the three protein preload trials compared to the water trial (P < 0.0005).

Visual Analogue Scale Data

Due to gender differences in energy intake at the test meal, all visual analogue data were analysed separately for male and female subjects. The VAS results reported are only for the post preload period. The VAS scores following the ad libitum test meal are shown in the Figures but have not been included in the statistical analysis.

Hunger

Men: Immediately following the preload, there were no differences in change in hunger scores from baseline between the trials (Figure 5a). However, at 30 min, 60 min and 90 min after the preload (immediately before lunch) there was a significant linear relationship (P < 0.05) between the protein content of the preload and the change in hunger from baseline scores.

Women: There was a significant linear relationship between protein content of the preload and change in hunger scores from baseline immediately post preload and at 30 min, 60 min and 90 min post preload (P < 0.05) (Figure 5b). Hunger scores were higher in the water trial than in the 12.5% and 25% protein trials at 30 min, 60 min and 90 min post preload (P < 0.01) and higher than the 50% protein trial at 60 min and 90 min post preload (P < 0.05). Fullness

Men: There were no differences in change in fullness scores from baseline between the trials (Figure 6a). No linear relationship existed between the amount of protein in the preload and change in fullness scores.

Women: Immediately after the preload, there were no differences in change of fullness scores between the trials (Figure 6b). At 30 min post preload, fullness scores were lower in the water trial than in the 12.5% protein trial (P <0.05). Fullness scores were lower in the water trial than in all three protein trials at 60 min and 90 min after the preload (P < 0.05). There was a significant linear relationship between the amount of protein in the preloads and the change in fullness scores from baseline at 60 min and 90 min following the preload (P <0.05).

Desire to Eat Men: Immediately following the preload and at 30 min and 60 min following the preload, there was a significant linear relationship between the amount of protein in the preload and change in desire to eat from baseline scores (P < 0.05) (Figure 7a). This relationship was not present at 90 min after the preloads (immediately prior to lunch).

Women: There was a strong linear relationship between protein content of the preload and change in desire to eat from baseline levels immediately following the preload and at 30 min, 60 min and 90 min after the preload (P < 0.05) (Figure 7b). Desire to eat scores were higher in the water trial than in the 12.5% and 50% protein trials immediately post preload (P < 0.05) and higher than all protein preload scores at 30 min , 60 min and 90 min post preload (P < 0.05).

Thirst

Men: Following the water preload, male subjects reported to be less thirsty than following the three protein preloads (P < 0.05). This effect was only observed immediately after finishing the preload (Figure 8a). Women: Immediately following the water preload, thirst scores were lower than following the 12.5% and 25% protein preload (P < 0.05) (Figure 8b). Thirst scores were lower 30 min after the water preload than in the 25% and 50% protein preload trial (P < 0.05). Differences between trials did not persist longer than 30 min.

Other VAS Measurements

There were no differences between trials in the VAS scores for the other questions asked for either the male or female participants (Table 3). There were also no differences over time for any of the variables.

Taste Test

Subjects rated how pleasant they thought the test meal was both at the beginning of the meal and when they had finished. There were no differences in the ratings before and after the meal for both the male (Figure 9a) and female subjects (Figure 9b).

Discussion

The primary aim of the present study was to investigate whether a dose response relationship existed between the amount of whey protein present in a liquid preload and food intake at a subsequent meal. It was hypothesised that increasing the percentage energy from whey protein in the preload would decrease appetite and reduce subsequent food intake at an ad libitum meal at lunch time. Male and female subjects were included in this study as it is unclear whether the responses to different concentrations of whey within a preload would differ with gender.

The results of the present study show that the responses to the preloads did differ with gender. Both male and female subjects did show a significant linear relationship between the amount of whey protein consumed in the preload and energy intake at lunch time, however, the differences in energy intake between trials were considerably different in men and women. There were no significant differences in energy intake in the three protein trials for the female subjects and they only significantly reduced their energy intake at lunchtime following the 50% whey protein preload when compared with water. Male subjects showed a significant decrease in energy intake following the 50% whey protein preload compared to water and the 12.5% and 25% whey preloads. When the energy content of the preload was taken into account, there were no significant differences in total energy intake between trials for the male participants. However, it is important to highlight that the total energy intake in the 50% trial was less than when water was consumed as a preload.

However, in contrast to the male participants, total energy intake throughout the experimental protocol for the female participants was significantly greater in all three protein preload trials compared to when only water was consumed mid morning. It therefore appears that the male subjects were able to partially compensate for the energy intake mid morning by reducing their energy intake at the test meal whereas the female subjects did not show any compensation resulting in a greater overall energy intake in the protein preload trials.

It is unclear why these differences exist between male and female participants however there are several points that must be considered. Firstly, the energy content of the preload was 390 to 410 kcal for both the male and female participants. Average daily energy intake for the subjects was estimated from 3 day food diaries completed by the subjects before commencing the study. The average energy intake was 2432 ± 588 kcal for the male participants and 1920 ± 478 kcal for the female participants. The preload therefore provided a larger proportion of total energy intake for the females than for the male participants. It is therefore possible that the energy content of the preload was simply too large to observe any effect of the whey protein in women.

Interestingly, the visual analogue scale data suggests that the female participants were more sensitive to the fact that they consumed no energy in the 0% protein trial. It can clearly be seen from the figures for hunger, fullness and desire to eat that female participants reported to be significantly less full, more hungry and had a stronger desire to eat following the water preload. In contrast, there were no significant differences between these ratings for the male participants. Despite this, females did not alter their energy intake at lunchtime accordingly but the male participants did. Although all the subjects recruited for this study scored below the cut off point for restrained eating in the Three Factor Eating Questionnaire, it is possible that the female subjects showed some restraint in their energy intake at the test meal thus explaining the similar energy intakes.

Further investigation is therefore required into the differences between ad libitum food intake between males and females within this experimental setup.

In conclusion, the results from this study show that a dose response relationship does exist between the amount of whey protein in a liquid preload and subsequent energy intake. However, further investigation is required into preloads with a reduced energy content which would be more representative of a mid morning snack, and whey protein contents that realistically could be provided in a snack. This work is currently underway at the University of Nottingham.

Table 1. Composition of the liquid preloads

Table 2. Composition of one portion of the pasta test meal

Table 3

Claims

Claims:

1. The use of at least 1Og of protein in the manufacture of a snack food comprising from 300 to 450 kcal for use in weight maintenance in a male human.

2. The use as claimed in claim 1, wherein weight maintenance is achieved by reducing the calorie intake at a subsequent meal.

3. The use as claimed in claim 1 or claim 2, wherein the protein is whey protein.

4. The use as claimed in anyone of claims 1 to 3, wherein calorie intake at the meal is reduced proportionally to the amount of protein present in the snack food, and by at least 300 kcal.

5. A method of reducing calorie intake in a male human at a meal comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og protein prior to consuming the meal.

6. The method of claim 5, wherein the snack food is consumed from 1 minute to 120 minutes prior to the meal.

7. A method of weight maintenance for a male human comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og protein prior to consuming the meal.

8. A method of weight loss in a male human comprising consuming a snack food comprising from 300 to 450 kcal and at least 1Og protein prior to consuming the meal.

9. A snack food comprising from 300 to 450 kcal and at least 1Og of protein for reducing calorie intake at a subsequent meal in a male human.

10. The snack food of claim 9, wherein the protein is whey protein.

11. The snack food of any one of claims 9 or 10, wherein the composition further comprises fibre.

12. The snack food of claim 11, wherein the fibre is present in an amount of 6 to 25g.

13. The snack food of any one of claims 9 to 12, wherein the calorie intake at the subsequent meal is reduced proportionally to the amount of protein in the snack food.

14. The snack food according to any one of claims 9 to 13, wherein the protein is present in an amount of from 10 to 50g.

15. The snack food of any one of claims 9 to 14, wherein the composition is liquid, semi-solid or solid.

16. A dietary regime for weight maintenance in a male human comprising consuming a snack comprising from 300 to 450 kcal and at least 1Og protein between breakfast and lunch, and/or lunch and dinner.

17. The dietary regime of claim 16, wherein the snack is consumed from 1 minute to 120 minutes prior to lunch and/or dinner.