The fad diets that do work.
Another day, another diet or so it seems in a world in which diet headlines are guaranteed to draw the interest of plenty of eager readers.
Fad diets, or those which are enormously popular for relatively short periods of time come and go, The Cabbage Soup Diet, Israeli Army Diet and the Lemon Detox Diet are just a few which have held the limelight albeit briefly over the past few years. What may surprise you is that a number of these diets do actually work, even long term if they are followed the right way. So of the popular diets of the moment, here is the lowdown on some of the more effective options.
Ketogenic diets are not new. Rather they have been utilised in medical settings to manage a range of clinical conditions for many years.
A keto approach requires followers to reduce their carbohydrate intake to an extremely low level so that ketosis or fat burning is induced as the body breaks down fat stores directly to be utilised as fuel. A keto approach requires followers to replace carbohydrate intake with fat, so the overall diet profile features <10% of energy from carbs, up to 70-80% energy from fats and just 15-20% of energy from protein. This is why you see a lot of avocado, butter, eggs and cream utilised in keto diets.
The reality is that most diets that claim to be ‘keto’ are actually just low in carbohydrates as opposed to achieving these ratios of fat, protein and carbohydrate. In real life, achieving these ratios in your diet is somewhat challenging but if you can, and do follow it, it will work very effectively.
Unlike the keto approach which requires strict carbohydrate restriction, the inclusion of fruit and some starchy vegetables including sweet potato see the macronutrient ratios of Paleo shift to a reduced carbohydrate rather than the low levels seen in keto, or between 20-30% of total energy coming from carbohydrates. The focus on fresh, unprocessed food naturally supports weight loss, as does the complete avoidance of processed carbohydrates.
The only down side tends to be an especially low intake of dietary calcium and while fibre intake from vegetables and fruit may be adequate, a number of followers find the lack of insoluble fibre intake from grains and legumes can result in constipation.
Very Low Calorie Diets that generally utilise meal replacement products and diet shakes to achieve an extremely low calorie intake of just 800 calories per day have again been used for many years in clinical settings to achieve weight loss. Now commonly utilised by weight loss surgeons prior to surgery, VLCDs are extremely effective in reducing fat stores in the liver whilst also inducing ketosis as overall calorie and carbohydrate intake is extremely restrictive.
VLCD’s work extremely effectively but the issue is that once they are ceased most if not all weight tends to be regained unless underlying eating habits are significantly altered long term.
Fasting diets, or specifically the fasting regime that requires followers to commit to two very low calorie (<500cal) per days each week have been shown to be effective in supporting relatively slow (1-2kg a month) weight losses. It appears that significantly restricting calorie intake for brief periods has a number of metabolic benefits in the body which in turn support fat metabolism. The biggest issue is that you will not lose weight as quickly as many desire.
The main difference between a low carb diet and keto diet is the proportion of protein the diet contains with low carbohydrate diets still requiring <10-20% of calories from carbohydrates but with more room for dietary protein that strict keto does.
Low carbohydrate diets, or diets that require followers to eliminate virtually all bread, rice, cereal, pasta, fruit and starchy vegetables are extremely effective in achieving fat metabolism, at least in the short term. The issue for most is that as soon as any of these high carb foods are reintroduced weight tends to be rapidly regained and becomes more and more difficult to lose in subsequent attempts.