Low carb diet was initially used in the 20’s as a therapeutic cure for epilepsy. In the 60s it was adopted by health practitioners for treatment of obesity. Atkins took it mainstream with his low carb – high protein – low fat diet. The new form of this diet, the keto diet, now promotes high fat with moderate proteins intake. Essentially, this is a high fat diet.
This keto diet is the new rage amongst people trying to lose weight. Some people swear by it and say that fat melts like crazy IF, and this is a big ‘if’, you are able to stay within the recommended carb limit for NOT DAYS BUT WEEKS. If you can do that then you have unlocked the secret to lifelong fat loss. It sounds dreamy, no?
So I decided to put it to test. But, wait.
We are getting ahead of ourselves. First lets look at:
What exactly is a low carb diet and how will it ‘melt away’ my fat?
In a typical low carb diet, the carb intake has to be limited to no more than 30g per day. Atkins diet is as low as 20g while others vary with upper limit of upto 60g per day.
To put this in perspective, consider this – a slice of white bread OR a whole apple contains 15g of carbs. A regular person consuming 2000 calories would on an average consume about 225 – 300g of carbohydrates per day.
The theory is that carbs can be rendered useless to the body if you can make your cells efficient at burning energy from fat (that get broken down into ketones, hence the name ‘keto’ diet).
You do this by exhausting your carb stores (carb is stored as glucose) so that it primarily harnesses your stored fat for energy.
This is when you will apparently see all the fat melt away from your body. As with all diets, there are side-effects to doing this long-term. But if only a few weeks promises a few inches off the waist, then it is a very interesting prospect to explore.
I decided that it was time to put this diet to test. My husband thankfully agreed to do the diet (actually he was more than happy, the prospect of fat melting away will make you agree to anything! 😀 ).
I have to tell you that creating a meal plan around this diet was a NIGHTMARE! I could only barely keep the plan under 30g of carbs and tried to put in as much fibre as I could.
The diet was created keeping a 20% deficit in the total calorie requirement. Foods with high carbs but low calories (like tomatoes, onions, cucumber, etc) had to be sacrificed to make way for more energy dense foods.
Whatever little carbohydrate I could afford to add to the diet, I needed it packed with fibre which means milk (my husband and I love our glass of milk!), had to be sacrificed (it has 12g carbs and ‘0’ fibre :/ ).
I was dreading my husbands reaction when I told him the diet plan, instead he was sceptical if he could actually eat ALL THIS FOOD IN ONE DAY!
Day1 and 2 went without any hiccups. By Day 3, he told me that he could not stomach any more paneer (Indian cottage cheese) and if we could substitute it with eggs. Morning of Day 4, we noted his weight and by the end of Day 4 he had had enough. The experiment was then discontinued.
He lost 1.8KGS IN 3DAYS on this diet and was one of the few lucky ones who got away with decrease in body fat and increase in skeletal muscle mass.
The backlash or the aftermath of the diet was not very pretty though. Thursday night we had dinner home delivered from our favourite Indian restaurant and he was ecstatic to just be able to eat roti (whole wheat Indian bread) and salad again! 😀
I felt like a monster to make him go through such an ordeal but he is a sport! 😉
We do have a good laugh now about his craving for roti and even something as simple as a glass of milk! 😀
So, the answer to the question, ‘will you lose weight on this diet?’, is clear:
YES, you will lose weight BUT you need a lot more variety in food to work with, if you want to make it work for more than a few days.
Can I do this low carb diet for a short period, lose weight and then go back to my normal diet?
This was one of my first questions. The ‘short period of time’ for this diet would have to be minimum 1 week. Even then expect 2-5 kgs of weight to come back. This is because for the first few days as your carb (i.e. glucose) stores deplete, you lose water from your body.
Essentially, the glucose molecule binds 3 water molecules. Once the glucose is used up it detaches from water which is then expelled from the body. To know more you can read this article about the Different Types of Weight Loss And Which One You Should Aim For.
As you go back to your ‘normal’ diet, the glucose reserves are restocked and they are able to hold that water again.
As expected my husband gained the 1.8 kgs back in 3 days. It was not all that bad though, his body composition did change and showed that he had lost about 0.7kgs (or 1.5 pounds) of fat.
Please note that loss of muscle mass is higher in Low Carb Diets particularly (Ref2). You might be able to save some lean mass by also continuing with strength training sessions 2-3 times a week but it will not be easy.
Are there any side-effects even in the short term?
Some people have reported mild flu like symptoms, headache, nausea, low energy and irritability. You experience this for 2-3 days as the body switches over to fat burning and after that things settle down.
The main problems that will not go away are bad breath and also for some people – constipation (because of the very low fibre content of the diet). Also research suggests that the inflammatory risk increases on this diet because of the high number of ketones in the blood (Ref3).
So what do we take away from all of this? Is it good, can this is done?
1. While it is true that we could do with less carbs in our diet, the first things we need to cut out are sugar and refined carbs. After these, as long as your macronutrients cover your fibre requirement, essential fatty acids and essential amino acids you only need to focus on eating less calories per day to lose weight.
2. In the name of low carb, don’t remove fibre rich sources like fruits, veggies and whole wheat products from your diet only to give in to cravings of pizza and sugar. Carbs are not the enemies, consuming EXCESS CALORIES is the problem.
3. Follow this diet, if you have hit a weight loss plateau (cannot lose weight despite cutting calories and staying active) or if you are obese (i.e. have BMI of 30 or more).
Related: How Much Exercise Do You Need
If you don’t meet this criteria but still want to try this diet, I would suggest that you keep the carb intake of upto 60g so that you can leave this diet with your sanity intact. :/
4. Lastly, these ‘fad diets’ are cannot be part of a sustainable weight loss plan. From Atkins, Paleo, South Beach, Alkaline to Micro-biome- they all have figured out only one variable of a very complex multi-variate equation that is the human body.
The scientists still do not understand all the channels and back-up channels through which the body sustains itself. And until they do, the only safe way (with no side-effects) to lose weight, and to lose it permanently, is to eat smart, refuse to feed your emotions and always stay active.
PS: If you do try this diet for more than a few days, it is advisable to take vitamin and mineral (esp. magnesium) supplements.
Ref1: Samaha FF, et al. Low carbohydrate diet as compared with a low fat diet in severe obesity. N Engl J Med 2003; 348:2074-81
Ref2: Meckling K.A, et al. Comparison of a low fat diet to a low carbohydrate diet on weight loss, body composition, and risk factors for diabetes and cardiovascular disease in free living, overweight men and women. Journ Clin Endoc Met. 2004. 89(6)
Ref3: Johnston CS, et al. Ketogenic low-carbohydrate diets have to metabolic advantage over nonketogenic low-carbohydrate diets. Amer Soc Clinc Nutr. 2006. 83(5), 1055-61