Yeah, it is - at least for the vast majority. Unless you've repealed the first law of thermodynamics, if you burn more energy (calories) than you consume, you will lose weight. You can't get something from nothing.
You are correct, of course.
What happens though, is the first 20 or 30 pounds is “easy”, and then after that it gets tougher, the body starts to slow metabolism down, and due to the fact that less calories are necessary to operate at the new weight.
I shed 60 pounds in about 6 to 8 months and found a stubborn few plateau levels along the way. It is kind of bizarre, because by a strict calories in calories out equation, it shouldn’t be possible to hang around at a specific number for days on end. At first my average was about 2 or 2.5 pounds every 10 days, but as time went on the average dropped to about 1.5 to 2 pounds a week or maybe a little less.
The key is persistance, because it is calories that count but it takes some time to get a “good head of steam” built up and start watching the numbers decline on the scale, but I think the advice generally given to people is a bit on the optomistic side. Truly sedentary people need very little food intake, and many foods are packed with calories, carb laden or not.
A tablespoon of peanut butter takes an hour of brisk walking to burn off! Exercise isn’t gonna make a huge difference if someone isn’t paying close attention, and to my way of thinking, as much as I love peanut butter, it ain’t worth an hour of walking just to add another dollop. Once I got a scale and started weighing portions and looking at calorie info on common food ingredients it opened my eyes.
Put another way, I’m not going to overeat and then try to exercise it away. Once in a while, I used to make biscuits and sausage gravy, hash browns, eggs, bacon etc. i added it up, and it could approach 4000 calories.
That’s literally enough to run a marathon, and that wasn’t happenin’. More likely a nice long nap. So the mystery of how I porked out there for a while, I think it’s solved! Reg’ler Sherlock Holmes, I know.
“Unless you’ve repealed the first law of thermodynamics”
Nope. Doesn’t even come CLOSE to working that way! That law applies to a CLOSED SYSTEM. Period. No human is a closed system. No human absorbs all the calories that enter their mouth. Much goes out the other end. And no human burns calories by actual burning. We convert them into energy, and that is done at varying rates of efficiency. Pima Indians have incredible rates of obesity and diabetes, and it AIN’T based on eating!
Many of us have known people who could eat anything and struggle to maintain weight. I can gain weight breathing deep while near a donut. My sister is in between, although her closest friend in high school had to eat like a horse just to stay above 90 lbs.
All of us are affected by hormones. Those hormones affect how we process food, how efficiently we use energy, etc. You might as well pretend all cars get the same gas mileage.
How we store weight differs too. People who are insulin resistant tend to convert more energy to fat and tend to “lock it up” in a way others do not.
“Adult weight gain and obesity are well-established causal risk factors for the development of type 2 diabetes mellitus, cardiovascular disease and obesity-related cancers [1,2,3]. In line with these findings, adult weight gain was strongly associated with increased insulin resistance in multiple studies [4,5,6,7,8,9].
It is well-established that abdominal adiposity, and in particular visceral adipose tissue, is strongly related to insulin resistance and risk of type 2 diabetes mellitus, also after adjustment for total body fat...
As shown in Figure 1, each higher category of change in body weight during adulthood was associated with higher fasting and postprandial glucose and insulin concentrations at middle age, after adjustment for sex, age, BMI at age 20, ethnicity, education, smoking, alcohol consumption, physical activity, and family history of diabetes.”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832997/
NOTE: The problem is they have it backwards. They think weight gain CAUSES the problem when it is the PROBLEM THAT CAUSES THE WEIGHT GAIN! And yes - hallelujah! - there is an approach that gradually deals with the root problem!
I’ve spent most of my life fighting fat, to include running 5 miles a day for most of my adult life. I believed the calories in/out theory and believed all the dieticians who told me a low-fat diet was the way to lose weight. I’ve never been VERY obese with a BMI running from 22-29.(Normal weight = 18.5–24.9 / Overweight = 25–29.9)
Three years ago, I read The Obesity Code. Then read Gary Taubes’ “Good Calories, Bad Calories” and “Why We Get Fat: And What to Do About It”. Then “THE BIG FAT SURPRISE
Why Butter, Meat & Cheese Belong in a Healthy Diet” by Nina Teicholz.
When I applied it, it began to work. Not instant weight loss, but three years later my waistline is the best it has ever been. UNLIKE EVERY OTHER DIET I TRIED SINCE 1972, IT WORKED!
If I sound like a zealot, I am! I spent my life fighting, telling myself I just needed to eat less and run more (than 5 miles a day) - and it didn’t work. Now I’ve seen gradual success, after all those years, by changing WHAT I eat, not by counting calories!
Lots of videos here:
https://www.youtube.com/user/lowcarbdownunder/videos