Week 7: Losing water weight post surgery

Weight (7d avg): 188.8.2lbs/85.6kg, from peak -10.9lbs/-4.9kg
RHR (7d avg): 56.6bpm
Calories In (7d avg): 1014kcal
Exercise (7d avg): 267kcal
Net Deficit (total): -6300kcal
3k run: 19:12 min

Notes:

This week started the day after my sleep apnea surgery. Because of the palate and tonsil reduction, eating solid foods was quite painful, especially after the first 2 or 3 days after the anaesthesia wore off. Eating was so painful, that I began to feel nauseous simply thinking about eating. In turn, this meant I could only take in a little over 1000 calories a day. My exercise also decreased, the small amount of cardio barely offsetting the general lack of movement from the days I stayed in bed. However, the did weight did fall off during this time period, dropping 3.7lbs (1.7kg) in a week.

But I knew this wasn't all fat I was dropping. More likely the reduction in food likely meant I was dropping water weight as I was both salt and carbohydrate depleted. The body stores carbohydrates as fuel in the form of glycogen and as stated in this article from the American Journal of Clinical Nutrition:

Glycogen is stored in the liver, muscles, and fat cells in hydrated form (three to four parts water)

That means while in a calorie deficit, especially when carbohydrates are limited, your body depletes its glycogen stores and the water it holds; one of the reasons ketogenic diets see such immediate weight loss within the first two weeks of dieting.

Ketogenic diet users can expect to lose up to 4.5 kg of body weight in the first 2 weeks or even sooner. For the most part, this is due to reduced water retention in the body, which in turn is mainly attributable to low carbohydrate supply, which is intrinsic to this particular diet....It is generally assumed that 1 g of glycogen is associated with at least 3 g of water (2.7 to 4 g). Assuming a 1:3 ratio, a loss of 500 g of glycogen will be accompanied by a loss of approximately 1500 g of water. Thus, the combined effect will be 2 kg of lost body weight. In addition, insulin is known to affect sodium retention in the kidneys, so a reduction in insulin concentration (as observed with the KD) will reduce sodium retention, which in turn leads to increased water excretion by the kidneys

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