Matt, can you tell me the difference between the Adonis principles and the Weight Watchers Flex program?
Flex program
The Flex system is, in essence, a simple way to quantify a participant's caloric intake and energy expenditure. Various servings of food are assigned a specific number of points, and various types of exercise are assigned negative numbers of points; a program participant is allocated a certain number of points per day, with that number based on the individual's current weight and weight goals.
The effect of this is that the participant is not restricted from eating any specific type of food, but they must stay under their total point value for the week. This stands in marked contrast to diet approaches such as the South Beach diet or the Atkins diet, under which some foods are completely forbidden and others are permitted in theoretically unlimited amounts. The participant's ability to factor exercise into the plan increases its flexibility: the participant can eat more points as long as they offset them with exercise, or eat fewer points if they prefer not to exercise.
Many Weight Watchers proponents enjoy the Flex system precisely because no food is out of bounds, as long as it is eaten in moderation, and because exercise can be factored in. (In the UK, Weight Watchers advertises under the slogan "Where no food is a sin"; this is a reference to its chief competitor Slimming World's system of giving some food "sin" values.) Others, however, dislike the record-keeping that the plan imposes on the participant, who must essentially keep track of the points value of everything they eat; they prefer other plans that place restrictions on types of food rather than amounts of food.
[edit] The POINTS formula
The formula for calculating the POINTS content of a specific food serving uses a formula described in US Patent 6,040,531:
p(c,f,r) = \frac{c}{50} + \frac{f}{12} - \frac{\min\{r,4\}}{5}
Where p is the number of points, c is the number of calories, f is the grams of fat, and r is the grams of dietary fiber (if the dietary fiber is greater than four, use four). The POINTS value is always an integer, with fractional values rounded to the nearest point. (An alternative format, mentioned in the patent and used on some websites, rounds values to the nearest half-point.)
The above formula can be expressed in OpenOffice.org Calc as follows:
=(B1/50)+(B2/12)-(IF(B3>4;4;B3)/5)
Where B1 is calories, B2 is fat in grams, and B3 is fibre.
This looks very complicated, but it should be emphasized that new U.S. members are given a cardboard slide rule: by reading the U.S. nutrition label on any food package and quickly adjusting three of the slide rule scales for Calories, Fat, and Fiber, the points are easily determined by inspection of the fourth scale.
A small paperback book is available for purchase that lists thousands of foods for sale in Fast Food outlets, restaurant chains, and even generic restaurant foods, e.g. "Mexican: Refried Beans, 1/2 cup" and the corresponding point value. This is for use in cases where the nutritional label is not available.
An early version of the POINTS system did not limit the fiber "credit" to four grams. Another variation, which may be explained by rounding, is that the "POINTSfinder" manual calculator distributed at Weight Watchers meetings does not reach a POINTS value of 2 until after 70 calories have been reached, rather than 50 as the formula would indicate. As a result, point boundaries are 20 calories (or 4.8 fat grams) higher than might be expected. Though the patent mentions possibly using 70 rather than 50 as the single point baseline, that method is said to be intended for use by dieters who do not use fiber as a "point enhancer" (reducer).
More recent versions of the program, such as that described in US Patent 6,878,885, take exercise and physical activity into account to grant additional points in the daily allowance.
In Europe and some other areas or countries, including Australia and New Zealand, the nutrition labels are markedly different; in particular they normally show kiljoules rather than calories, and may not include fibre. Thus, the POINTS formula varies and it calculated only from energy (as kilojoules) and saturated fat. This formula is expressed in UK Patent 2302605 as:
p = \frac{e}{k1} + \frac{f}{k2}
Where a is the number of points, b is the energy value, and zx is the grams of saturated fat. The constants are k1 and k2 are described as such: k1 is chosen so that the points target will be in the low tens. If the energy value is to be entered in calories, then k2 will be within the range of k1/35 and k1/10, ideally k1/17.5. If the energy value is defined in kilojoules, then the value of k2 will be between k1/146.7 and k1/41.8, ideally being k1/72.8.
A practical implementation of this formula for a kilojoule-based calculation appears to be:
p = \frac{e}{300} + \frac{f}{4.12}
The resultant value, p is then rounded to the nearest half.
[edit] Plans
[edit] The Core Plan
In part as a response to the popularity of plans like Atkins and South Beach, Weight Watchers has recently developed a separate plan, known as the Core Plan. This plan classifies certain types of food as "core," and permits participants to eat core foods with the restriction that they should only eat these foods "until satisfied, not full." Core foods are a list of healthy foods from all the food groups, including fruits, vegetables, fat free dairy, lean meats, and whole grains. Non-core foods are assigned the usual point values, and participants are given an allottment of 35 non-core points that they can eat in a week.
[edit] The Flex Plan
Under this plan, participants are assigned a set number of points to consume per day based on their current weight. The number of points allowed may be increased with exercise. The "Flex" part of the plan is that several additional points are allotted (which is not based on weight) that can be used or not used during the week.
http://en.wikipedia.org/wiki/Weight_Watchers
