5:2, Acid-Alkaline, Atkins, Dukan, Paleo Ketogenic, Slim Fast, Slimming World, and Zone. All diets the 1/3 Brits constantly dieting may have endured.
Yet research from the UCLA shows “dieting is a consistent predictor of weight gain: 30-60% of people on diets see an increase in weight over 5 years.
It’s time to shed some light on why low-calorie diets are bad and kill them off once and for all!
So, imagine you are female – which is lucky given your name is Lucy – you are 25 years old and weigh in at 63.5kg (10st).
… and decide surviving on 1,000kcal p/day will get there.
Let’s investigate what that means in relation to Lucy’s Kcal Needs:
Using the Schoefield Calculation, Lucy’s total basic kcal requirement (Basal Metabolic Rate – BMR) =
14.8 x 63.5 (Weight) + 487 = 1,427kcal (+ or – 120)
Since Lucy has a sedentary office job at MarketingMasters123plc and doesn’t just lay in bed all day we apply a Physical Activity Factor to discover that sustaining her current weight at current energy expenditure – her daily kcal requirement is:
1,427 x 1.4 (inactive) = ~2,000kcal
So the 1000kcal diet is only 50% of what Lucy needs and is below her BMR!
Let’s investigate how her body will react:
Stage 1 – Quick Wins
Lucy’s body thinks she is starving and switches to survival mode! On day one of her diet she uses up glycogen stores in the liver and muscles for energy to protect vital organs. Since glycogen is stored in water (3g water for every 1g glycogen) she loses weight via water loss too. Imagine the total glycogen stored weighs 250g, that means on day one she loses:
250g Glycogen + 750g Water (3 x 250g) = 1kg (2.2lbs)
Stage 2 – Saving Energy
But because Lucy’s body is lacking the kcals needed it decides to sloooooowwwwwwwwww everything down by reducing her BMR by 20%. Lucy’s new BMR becomes:
1,427 x (1 – 20%) = ~1,140kcals
Stage 3 – Making Energy
Since Lucy’s intake of protein is so low, her body obtains the amino acids it needs by breaking down muscle protein already in her body. Muscle protein is also bound up with water (4g water for every 1g protein) so even if Lucy breaksdown just 100g protein she’ll lose a total of 500g (1.1lbs) in weight.
Weight loss by day 2: 1kg glycogen + 0.5kg lean tissue = 1.5kg (3lb)
Great right? WRONG! The weight loss is all from water, glycogen and lean muscle tissue!
Stage 4 – Pushing Through
Let’s say Lucy smashes through the hurt and hunger (the pancakes below look delicious but a tiny portion size!) for another 7 days. Her body, still in starvation mode, attempts to hold onto its fat reserves by reducing fat released and increasing fat storage.
Stage 5 – Plateau
A few weeks later, Lucy’s still super-hungry. Yet her early morning weigh-ins are relentlessly super-dissapointing – her weight doesn’t change! Her body has adapted to the new situation. Further weight loss will only happen if she goes down to <1,000kcal p/day. Lucy cuts to 750kcal p/day but in a few weeks plateaus again. Now what? 500kcal? 250kcal? 0kcal?!
Stage 6 – Failure!
The plateau is too much for Lucy and she returns to eating a normal 2,000kcal p/day. Problem is –the diet has changed her body and thinks she’s binging! It stores fat more readily and her BMR is lower. The net result? She now has less lean muscle and puts all the weight back on!
The bottom line – DIETS DO NOT WORK – DO NOT DIET. Luckily, the ‘restrictive or unrealistic’, diet plans and weight loss clubs have already started losing out to the broader healthy eating movement. It’s time we killed the diet once and for all!
Luckily, there is another way… See how Lucy gets on when she tries a new approach in ‘I F***ing Love Food'