The fast mimicking diet is low in a number of things, including total calories and protein. Valter notes in the below video that it’s not just what the diet lacks, it’s also about what the diet contains, that gives it the positive results.
The ProLon box contains a 118ml (4 fl oz) bottle of liquid, called L-Drink, for each of days 2 to 5. Based on your body weight, you decant a specified amount of the L-Drink into a water bottle, and dilute the rest with tap water. Then you aim to drink the whole thing throughout the day.
^ ProLon L-Drink – interestingly the orange flavour is cloudy and the lemon is clear – presumably due to the contents of the flavoring used
Valter describes the function of the L-Drink as being to provide an external source of glycerol. People who are in a fasted state naturally produce glycerol, and this is used for gluconeogenesis (the production of glucose (energy) from non-carbohydrate substrates like fat and muscle). Valter notes in the video below that after 3 ProLon cycles, when measured, people are found to have lost minimal amounts of muscle – and one of the reasons could be due to the L-Drink.
See the video below for more on Valter Longo discussing the role of glycerol: https://www.youtube.com/watch?v=vDNwcwRblIU
L-Drink Ingredients & Functions
- Purified water: Unlikely to form any function, other than as a base to mix the rest of the ingredients into, and then bulk them up for measuring out quantities
- Vegetable glycerine: As mentioned above, this provides the body with an external source of glycerol to aid in gluconeogenesis
- Natural flavor: To make more interesting to drink, and perhaps mask any uncomfortable taste from the glycerine
- Potassium sorbate: Whilst potassium is an electrolyte, it doesn’t seem common to choose it in sorbate form for electrolyte purposes. Therefore it’s most likely that potassium sorbate is included for preservative reasons – to extend the shelf life of L-Drink
How Much Glycerine to Use?
Whilst the L-Drink nor its labels say the exact amount (in grams) of glycerine they’re using, we can still use inference to calculate it with reasonable precision. I’ve turned this calculation into a calculator, which you can use below:
Below are the calculations I’ve used for glycerine quantities:
According to the L-drink label below it’s formulated such that the 120ml bottle contains 118 calories.
You then pour out the contents until you hit the mark on the bottle which represents your weight in kg.
Using a measuring cup, I checked and found that each mark represents the equivalent in millilitres (ml).
So for example, a 70 kg person is going to pour out 70 ml.
Therefore, using the total calories as a guide, we can see that 120 ml of the bottle contains 29.5 grams of glycerol.
This is because glycerol is very close to 100% carbohydrates, and 1 gram of carbohydrates equals 4 calories. So 118 calories divided by 4 equals 29.5 grams.
Working backwards from this, we can see that each kilogram of bodyweight would need 0.245 grams of glycerine.
Or, converting this to metric units, 1 lb equals 0.111 grams of glycerol. So a 154.32 lbs person (70 kg) again would use 17.13 grams of glycerine. (Yes, I lost 0.02 grams due to rounding, but this is close enough).
So a 70 kg person would need 17.15 grams of glycerine. Of course… measuring 0.15 grams is a fools errand, so we can round to 17 grams.
However, for preciseness, the calculator below using the more exact numbers.
Once you have calculated how much vegetable glycerine you would need per day, you can then:
- Measure this out each day on days 2, 3, 4 & 5.
- Add it to a water flask, and shake to mix. If it’s not mixing due to the water being cold, using warmer water may help with initial mix.
- Optionally add a calorie free flavouring. The L-Drink does this to improve palatability.
Is Vegetable Glycerine Safe?
Vegetable glycerine is commonly used in food & cosmetics. For example in food, it’s used to prevent icing setting too firm, and for making ice cream softer to scoop.
In a 2012 study into the effectiveness of glycerol for sports performance, they used a dose of 1.2 grams per kilogram of bodyweight for each study participant, with no noted adverse health effects1The Effect of Glycerol Supplements on Aerobic and Anaerobic Performance of Athletes and Sedentary Subjects – J Hum Kinet (2012).
1.2g/kg is a much higher dose than is used in ProLon.
For clarity – glycerine and glycerol are the same thing, however commercially it’s often referred to as glycerine, and inside the body as glycerol.
Where can I buy vegetable glycerine?
Many will be familiar with seeing glycerine available in supermarkets, typically in the baking aisle. It can also be found on Amazon and other online retailers. You can check if it is “food grade” just to be on the safe side.