You really can't fudge the numbers

Yes. And no. If you are trying to lose weight, the primary factor is going to be: creating a caloric deficit. The source for that is... basic science and nutrition. Pick Any book on nutrition used to teach at an accredited school. That’s my source there. As for the changing ways to produce energy... yes. And no. I think that may be a poor phrasing.

Calories are the sort of- primary “go to” macro nutrient that people tend to know. Salts and sugars and fats and saturated fat and trans fat and then carbs have been added to popular consciousness- with varying levels of understanding of what those mean.

You aren’t so much changing the way your body processes food as you are changing the food you put in your body. “Carbs” can be simply described as sugars. Not exactly like table sugar. But chemically they are sugars. But not all sugars are created the same, and not all are processed the same by the body. Some are very simple, quickly digested and taken into the blood and to the cells. Others more complex, “slower acting.”

Now, what you eat... I’m not doing the whole thing. Nutrition and chemistry are subjects that can take years to explain. But what you eat has all sorts of effects. The hormones that regulate your body are effected by what you eat, how much you eat, etc. Insulin produced when you eat had complex interactions with all sorts of things. Insulin isn’t just “that thing involved with diabetes.” Insulin has impacts on things like muscle growth- protein synthesis, there’s all sorts of interplay.

So you don’t exactly change the way your body processes nutrients by eating different things so much. It’s more that by changing what you eat, how much, when, etc- you can change the chemicals produced by your body which can change all sorts of things and processes in the body. The concept is basic to our understanding of nutrition. HOW changes impact our bodies and WHAT those changes do... there is data and anecdotal evidence that contradicts or isn’t conclusive and while some things are generally true about nutrition- how an individual person will react to any specific nutrition plan often varies greatly.

You’re really only going to see any advantage from changing to any diet if your own diet is in deficit or surplus- unbalanced for your needs- AND the new diet corrects those imbalances. Of course- it can, if it isn’t balanced itself, introduce new issues as well. But there is no conclusive evidence that low carb diets or “keto” diets offer any advantages other than what would be expected of a diet low in sugars etc. wether these diets have a positive effect on your body will depend on your physiology, lifestyle, and wether or not you were already consuming too much sugars and other things.

To the premise of the meme- caloric deficit is literally how the weight loss is achieved. When we talk about fitness or “looking better” we aren’t just talking about weight though. We are talking about body composition and such. The “keto diet” is similar to the classic diet of strength and power athletes and practitioners. Fats are one of the primary building blocks of hormones. The human body needs some fats to function well. Protein is used for tissue repair and new tissues among other things. Sugars, like carbs, are easily processed by the body and quickly converted into a form usable by the cells for their energy needs.

Nutrients the body cannot use at a given time are, are much as possible, stored by the body for later use. This is usually stored as fat cells the body creates from excess nutrients. Because sugars are easy to break down and more easily made available to cells, consuming large amounts of sugars containing a surplus of calories the body doesn’t immediately need- will most often result in some excretion but largely in creating new fat storage. The other process that will occur, is that a sudden spike in blood sugar will (in a healthy person) trigger an insulin response from the body, which starts a cascade of hormonal and other activity all over the body in all sorts of tissues and systems.

Again- the interplay here can get very complex. But in short- a “healthy” and “average” body will react in a relatively predictable fashion to the intake and digestion of given nutrients in given amounts over given time periods for a given physiology and given activity levels.

So there isn’t “bro science” or anything afoot. Weight loss is LITERALLY (in an “average healthy person”) dictated entirely by a calorie deficit being maintained between an upper and lower limit based on the individual.

As for specific diets changing how you process nutrients etc... that claim is dubious. It is more accurate to say that how your body reacts to certain substances and factors is somewhat standardized, and certain combinations of nutrients and intake/lifestyle factors can be used to control the way the chemical and physiological responses of your body carry out their processes, and if done right can help achieve a goal.

Long story short- most “fad diets” are designed in these principals:
1. Generality: a “true” diet plan is individually tailored to a single persons lifestyle and physiology (and goals..). An optimized diet plan will involve lab work and other diagnostics before the diet plan is initialized, and during the course of the plan to monitor response. The minimum tools for an informal personal diet plan would be careful documentation, a mirror, calipers, scale, measuring tape, and possibly photographs. Fad diets tend to be designed so that they don’t work particularly well for any one person but can be applied to most people with some level of results.

2. Simplicity: fad diets tend to be designed to be simple. Instead of trying to impart an understanding of complex mechanisms and chemistry, or even a basic understanding of nutrition- most diets simply go with a “this is good, this is bad” approach- or just outright give you lists of what foods you can eat and how much and how often. Sometimes to extremes such as “only eat beans, rice, and grapefruit...” they’re usually designed around the idea that I’d you follow the program, even if the program is somewhat poor, that you’ll hit a caloric deficit and still get most of the nutrition you need to survive.

3. Ease. Most such diets are designed to be easily followed. This is perhaps one of their greatest “tricks.” It isn’t exactly a trick. The secret to diet and exercise is that the one that works.... is the one you actually follow and do consistently. It’s very simple. If you drink 10 sodas a day and eat a large pizza for every meal- of every 6 months you get upset and go a well or even 3 months eating salad alone and drinking water- then go back to your old ways- you aren’t going to se the results over a lifetime you would just by cutting down by 1 slice and 1 soda a week or a month. Now- even eating 1 large pizza a day, and 5 sodas... you’re probably not going to be very healthy or on the cover of sports illustrated... but you’ll be way more healthier and weigh less than 3 pizzas and 10 sodas.

So creating diets people can stick to is the success of programs like weight watchers. Diets that give extreme success over short periods tend to be ones you literally can’t stick to. Can I you have the will power- long term the body can’t do. You can actually lose 10lbs in a week with “cleanse” type diets and fasting. It’s not really good for you- and you can’t do it week after week like if you wanted to lose 150lbs. And the weight tends to largely be water weight that you gain back as soon as you stop fasting... but it isn’t technically a lie....

Changing your diet away from carbs is firstly lowering your insulin production (as you stated, they're sugars). Beside splitting up sugars one of the most crucial functions of insulin is to trigger fat storage.
As carbs won't be available for energy production and insulin levels sink, your body starts to produce energy from stored fat and consumed proteins, which isn't done in the bowel, but in the liver. A low carb diet normally is based in a significantly increased protein intake, so that said, your metabolism is forced into a rather radical change.
The increased availability of proteins will then, alongside with physical movement aka sports, result in muscle growth and the more muscle you have, the more calories you burn, even when resting.
To conclude: if you strictly follow a low-carb diet, you don't need to cut calories to improve your bodily aesthetics.

@_@

Nutrition is very complex. When I was in my 20’s and lifting heavy weights, 6-7 days a week training, sometimes 12 hours training days- I’d eat entire birthday cakes by myself. I hit my proteins and fats and other goals and needed just calories. At one point I was eating 4,000 calories a day and losing weight. That doesn’t sound very healthy does it? Technically it wasn’t. But my metabolism and my training and other factors allowed me to do that when I was bulking, and then when cut time came I didn’t have to cut too hard, but I’d drop to very low calories, mostly protein and fat. Lots and lots of water to protect the kidneys and stay hydrated, and then before a weigh in or any time you needed to look cut- you drop the water and pretty much stop eating.

You can eat pretty lousy and get very buff. Unless you’re on gym candy or have very good genes and are young- you’ll have trouble gaining size and being lean on fat if you don’t nail your nutrition and cut all the garbage out. A healthy person not tying to compete or have the most fit physique can just be sensible, and pretty much anything you eat will be fine as long as you keep your ratios of fats/proteins/carbs sensible and stay around your maintenance intake of calories.

There is no Magic to “keto” or “paleo” or any of that stuff. Weight watchers points “gamify” and make very simple choosing a sensible diet for the day. They give you freedom and let you experiment to find times and portions and foods that you can live with eating- because success in diet depends on your diet being a lifestyle that you can stick to. Keto and paleo basically just have rules and often “bro science” to reinforce the basic food groups and proper ratios of those food groups. Most popular systems just label foods that are harder and more complicated to work into a balanced diet as “forbidden foods” and so you stay away from them and avoid the Pitt falls of them.

Finding the right diet, or fad diet- is just about tricking yourself basically. That’s all these “diets” do. I’m not knocking them necessarily. The thing is, there are so many systems and books and buzz words- and most of the somewhat decent ones are just giving you a basic nutrition program based of simple fundamentals of nutrition and then using marketing buzzwords and psychology to make you believe on the system. And if you want to believe and it works for you- more power to you. That’s why Jane can be in the best shape of her life and feeling her best and actually happy on the “Mesmo9000 diet” or whatever- and Jim can hate it or get bad results. Sometimes it’s your physiology- usually it is psychology and your ability to tolerate and stick to a diet.

And... well... a lot of times it isn’t so much that you need to lose weight. What’s the difference between Jim, who cuts to 900 calories a day and walks 30 minutes when he can or feels like it- and loses 10lbs, and Joe who eats 1800 calories a day but runs and swims and lifts weights and rock climbs and loses 10lbs? Joe probably looks better. Joe probably feels better. And joe almost definitely will do better at most tests of physical ability and everyday things like walking or climbing stairs.

As a matter of fact- if Jill Loses 15lbs by cutting calories from 2500 to 1000 and walking, and her twin Jane starts eating 3,000 calories and power lifting and cycling regularly, and gains 5lbs- Jane will probably feel better, perform better, everyday tasks will be easier, and almost anyone would agree Jane looks better. Because of Jane lost 10lbs of fat and gained 15lbs of muscle- she’s probably looking pretty good. By targeting her butt and legs, she can sculpt them and keep some shape and size even without the fat. Muscle in the upper chest helps give an appearance of lift to her breasts, shoulder and upper torso muscle help create an “hour glass figure” even with lower body fat- etc etc.

So wether gone any health or performance or looks- the scale is only part of the equation. Body composition is very important. Someone who is carrying 10 extra pounds of fat can look chubby or dumpy. That same person with the 10 extra pounds of fat carrying an extra 20+lbs of muscle is still beefy- not hard and lean- but they look completely different. And diet DOES play a role in body composition. If you aren’t getting enough protein- working out won’t build muscle tissue because you’re body doesn’t have the building blocks to do it. If you’re working out like crazy but you’re taking in lots of fast absorbing simple sugars outside your main windows of activity/ your body is still going to store those as fat.

And diet and exercise are both hampered when you aren’t sleeping and resting properly. Stress hormones like cortisol contribute to most peoples fat storage. Study after study shows correlation between accumulation of fat and poor sleep.

So it’s a shine complex thing and health is a lifestyle not a hobby. It can be a lifestyle AND a hobby, and hobbies can contribute to health (or hurt it), but ultimately health is a lifestyle to be successful and get lasting results. People who know this and can practice it don’t need or use pop diets. They already are doing what they need to do. Pop diets are set up to (make money yeah- but also to) make eating right simple, livable, and sometimes kinda “fun” for people who don’t want to or can’t wrap their heads around all the intricacies of the whole big picture. It can be overwhelming, confusing, often daunting, and this wall of text is a very simplified and very incomplete bit of the whole thing. And then- whatever generalities I say here might not apply specifically to you, because diet is individual. No one can tell you from across the internet or whatever, how many calories you need to eat to be healthy and lose weight. Not without knowing a lot more about you- and that’s....

IF you can give a truthful and accurate picture of your lifestyle and health. Which you probably can’t. Because most people can’t. That’s why people who know this stuff can make a lot of money just by following you for a day or so and giving you a spreadsheet that had a bunch of stuff that you could learn in a semester of night classes written on it. Because while we all may be different and some peoples lives and physiology or goals can provide genuine challenges- usually the answer to the most common nutritional problems or goals (“I want to lose weight/belly fat” being probably most common...) are simple no $hit things that really don’t involve “hyperkentosis” or “reverse hormonal osmosis” or some bro science about how I’ve discovered some “secret” of eating that no one figured out in 50,000 odd years of people eating $hit.

They all basically book down to:
>drink more water. Lots of water.
>try to pretty much only drink water.
>don’t drink booze, or drink way less.
>get up. Do things.
>eat less junk.
>eat less. Period. Just eat less.
>stop grazing like cattle. Don’t take a handful of chips here and a cookie there.
>less sugar.
>less lab food. It’s harder to predict what lab food will do. It’s just easier to say don’t eat trans fats than to try and figure out how to make that work in a healthy diet.
>don’t let yourself get super hungry because then you’re more likely to eat garbage. Or overeat.
>eat until your satisfied not stuffed.
>some how track or account for what you eat.

And all those diets use clever ways to convince you of awesome science or little games and gimmicks to do these things.
“Eat lots of tiny meals...” that’s mainly just a way to get you to eat smaller portions and to keep you in a state where you aren’t ravenously hungry at any particular point.
“Eat more proteins and complex carbs or...” asides proteins being one of the nutrients you need a lot of- complex proteins and complex carbs are slower digesting. This not only helps prevent spikes in sugars and insulin and the effects that has- but it also helps satiation. A lot of diet crap is aimed at satiation. Most people don’t like being hungry and won’t stick to a diet if they are always hungry. Water is important- especially if you’re taking in lots of protein- but water also has no calories (well.. it has some but... counts as none..) and helps fill your stomach.

Paleo, Keto, Atkins- not so long ago low fat low sugar diets were the fad. That’s basically what paleo and all those are. They limit the foods you can eat and make it very hard to take in large amounts of fat or sugars. It’s all the same stuff. There is no secret. If you understand how the body works, how cells work, how fat is made or burned, ATP, metabolic processes, hormones.... it’s all the same basic mechanisms and these diets are just different systems to get you to do the same basic things in different ways.

If it works for you- do it. Be as healthy and as fit as you want to be. I won’t knock these diets. There are things about them and the predatory industry, and how often the media and marketing hype around these things can spread disinformation and create problems- that’s another post for another day. The diets themselves in theory- most are reasonable and safe (consult a physician before starting a diet or exercise plan etc etc) and should work for most people if they can follow them and stick to them. So whatever works for each person. There isn’t any magic here though. It’s all fundamental and any widget loss not caused by injury or other phenomenon is going to be caused primarily by caloric deficit.

@f_kyeahhamburg- in simple terms your science is pretty solid. I mean, there are some exceptions and pocket cases and we could pick at terms- but overall- yes. But the conclusion- yes and no. If you cut carbs, you’re likely cutting calories. If you cut carbs and increase your other calories to compensate for the lost calories from carbs- you aren’t very likely to lose weight. If you take in 3000cal and burn 2800- the other 200.... your body doesn’t care what the calories are for the sake of weight gain by and large. Once your nutrition and energy needs are met- the excess is excess.

I will agree with you however that while when we ONLY talk about weight gain, what is of primary importance is the total number of calories, that what those calories are DOES have an effect on body composition and health as you say it does. Eating 300 extra calories of Twinkie a day will impact your health and body appearance in ways that eating 300 extra calories of broccoli won’t. The original post only says what the effect on weight loss is though, not the effect on nutrition, body composition, health, function, energy levels, or the ability to keep muscle mass while losing body weight.

So when you are cutting carbs, the primary effect on weight loss is simply the caloric deficit. If you drop 300 calories of carbs and start eating 300 more calories of fatty beef- if you aren’t on an exercise or activity program and your activity stays the same- you aren’t likely to lose much or any weight from the change. You can lose some- but there are caveats to that. The body will, at a point, pass excess protein through the kidneys. So cutting 1000 cal of carbs and adding 1000 cal of protein to a diet of a 300lb person with over 30% body fat- they’re more likely to lose weight from when they blow their kidneys out than from the diet. But one of the “tricks” of low carb diets is that being prevented from drinking sugary drinks and eating sugary foods and being banned from grain alcohols and many of the foods people commonly overeat and commonly carry “hidden calories” (fried potatoes and the oils and seasonings and high calorie sauces common to them, cakes and breadsticks

Chips aka crisps, and “grazing foods”) will almost always reduce a persons caloric intake by default, and keep them away from foods that are commonly overeaten or easy to lose track of your intake of and forget to include in your counts. So I mean... the main way that any diet indices weight loss specifically is just caloric deficit. Most people who are “just slightly to moderately overweight/high body fat” really don’t need or benefit much from synergies and things as complex as insulin factor and timing meals and stacking fast or slow acting proteins etc etc. it’s like having your family sedan tuned by an F1 shop- there is almost no benefit to the average person because they don’t do or have what is needed to really benefit from the precision there. Things like insulin release are less for Betty who needs to drop 10lbs and more for Bernice who has been training and on a nutrition plan for a year or so and is trying to drop from 17% to 15% body fat and needs the edge.

But like I say before- if it works for you it works. As long as your doctor says you’re healthy and getting what you need, and you like the results and it’s something you can live with- go for it. If not eating gluten makes you feel better after a week- wether that is in your head or not- you feel better. If a diet where you cut out a meal a day works, go for it. If you’re loving some new diet where you can only eat green foods and drink clear liquids and you’re healthy and liking it and sticking to it and like the results- go for it. At the end of the day- 90% of people just need to stay in their calorie range, eat less junk food and more staples, keep a ratio of protein/fat/carbs, and that’s it. If you want more you can track all your macros. If you want more you can make sure you’re getting all your vitamins and micros and such. If you live in a developed country, your foods are probably fortified and if you don’t do anything extreme with your diet- you’ll get all nutrition you need