Hey High Five! Today we are going to briefly discuss aggressive, but healthy weight loss and why we usually recommend low carb diets to achieve that goal. This is totally healthy and safe for almost everybody, but if you have concerns please speak to a physician first. I am not an expert on genetics or endocrinology, but I will do my best to clearly explain this process as I understand it. The hardest part during implementation is knowing what is in the foods we eat and getting used to the macro nutrient composition of common foods. The Meal Builder Spreadsheet has many foods already in it, so check that out as a place to start. You can also use the Nutrition Data website to find foods that are not on that list.
Our bodies have multiple ways to generate energy and are miserly with it by nature. Food used to be much tougher to obtain and every calorie is valuable in a survival situation. Our bodies respond to information about our environment (food, sleep, activity) by activating or deactivating certain genes that release specific hormones or create specific proteins for our cells to use. We cannot change the genes that we have, but we can influence which ones get turned on or off (think about that, it’s pretty cool!), and hence, our body composition. Intense exercise like CrossFit and heavy lifting (along with a balance of active recovery like walking and other light, easy activity) influence and support this gene expression, but today we are going to focus on food.
In a nutshell, a low carb diet turns the body from essentially a sugar burning machine into a fat burning one. Remember from previous posts what Basal Metabolic Rate is? It is the amount of calories you burn in a day just to live (creating heat, growing hair, etc.). What we do with a low carb diet is turn on the genes and cellular machinery to preferentially burn stored body fat for energy instead of carbohydrate. This is how people lose weight: using fat for everyday energy instead of carbs.
Why does this matter? The body can only store up to ~2000 calories worth of carbohydrate at a time (in the form of glucose or glycogen). And that would be for a 6’3″ 220-lb athlete. Most of us can store significantly less. And to add to this, a large percentage of that stored energy is in the muscles and cannot be accessed for other purposes. This means that most of us might have around 500 calories, give or take, of available stored glucose at any given time. And did I mention that most of the rest of that 500 calories is earmarked for the brain’s use? With all of us having Basal Metabolic Rates above 1000 calories, we have a pretty significant deficit.
Compare to stored body fat. A person weighing 150 lbs at 10% body fat has about 15 lbs of fat on them. Every pound of fat is ~3500 calories. So this person is quite lean already and has access to over 50,000 calories of energy via stored body fat. This is a simplified example, because there are different kinds of fat, but you get the picture. Fat is an extremely efficient way to store energy and tapping into that with diet is how to burn off the extra. Ok, cool. So now we get to the details.
Carbs: How many carbs should I eat? For aggressive weight loss, between 20 and 30 grams per day is great and will put you into dietary ketosis after a period of acclimation. You can go up to 50 grams if you want to ease into it. The energy switch does not happen immediately and you may experience some lethargy and sugar cravings at the beginning. Fight it! This is your body making the transition into fat burning beast mode! Because we are limiting carbs, you might not PR your Fran time while you’re doing this, but you will lose weight by activating the fat-for-fuel machinery in you body. How much is 20-30 grams of carbs per day, you ask? One apple. However, the good news is that non-starchy veggies like broccoli, onions, carrots, celery, etc. and greens are free. The fiber in them mostly cancels out the carbohydrate that they have and so eat as many of those as you like.
Protein: Moderate protein mostly in the form of meat, fish, and eggs. “Moderate” means eat around your lean body mass in grams per day, perhaps a little less. Your body is actually pretty good at knowing how much protein it needs, don’t make yourself sick just to hit a number.
Fat: Eat a lot. Butter, olive oil, coconut oil, animal fats, avocado, heavy cream, olives, and nuts (in moderation and not peanuts). All of these are great and will help you feel full throughout the day and support the transition.
Little things: coffee is cool, especially blended with butter or heavy cream. Salt your food or you might get headaches. Drink water when you are thirsty.
Whew. Thanks for hanging in there for the whole post! There are a lot of details and nuances that had to be left out, but this is the basic template for aggressive weight loss. Slower weight loss can be done with 80-100 grams of carbs per day and effortless weight management with 125-150 grams per day for most people. Give this a shot and definitely talk to the coaches and post in the Facebook group for questions and ideas for how to make this work!