1. The usual food and drink of a person or animal.
2. A regulated selection of foods, as for medical reasons or cosmetic weight loss.3. Something used, enjoyed, or provided regularly
A diet-with-respect-to-food, for me, is a combination of all three of the official definitions. A enjoyable, sustainable regulation of intake that constitutes your usual food and drink. The concept that you can go 'on a diet' for a temporary period of time and expect it to have long-term results stops making logical sense after I process the word temporary.
My weight is my weight, and your weight is your weight. Even if there are health issues involved, or there is a lack of access to food that doesn't screw up your body, or you have psychological issues and damage as a result of any number of chronic or acute mental traumas, or you have low activity (for whatever reason), or any other factor that makes up your weight, your body is doing the best it can with the tools it has. Don't hate on your body for doing what bodies are designed to do.
Sometimes your body wonks out, trips a circuit breaker and goes haywire, or starts breaking down. Your body is a collection of algorithms, processes, responses, reactions, and automations. It doesn't necessarily know how things are going to turn out for you 10 years down the road, but it sure as hell is trying its best to run right now no matter the circumstances. Your meatsuit is gamely trying to keep up with everything happening that makes it respond and adapt.
The cumulative algorithm analogy, of course, works best under the assumption that you are not your body. That your totality cannot be expressed with the physical alone and, even further, that your physical is not under your direct conscious control. Treating the body as a machine, computer, or vessel works from the fundamental idea that human beings are greater than sum of their parts, that a human's gestalt incorporates the body, but is not defined by the body.
To be absolutely fair, certain disciplines can (or at least claim to) give you amazing conscious physical control over usually automatic processes. However, for me and most of the people I know, our bodies are like our cars. I know how to change oil and flat tires, but the intricacies of the timing belts for an interference engine is a little beyond my immediate capability or interest. Additionally, this viewpoint is based heavily on the mind/body dichotomies or mind/body/soul trichotomies of western thought.
My point is that the best diet is a sustainable lifestyle change. It's not an isolated thing. Every algorithm your body uses to determine weight and health has hundreds of variables, some as blatant as 'I ate a Big Mac every day for forty years and I feel fine' and some as subtle as 'I function better in dry climates or low altitude'. As Dianne Sylvan (in the post that prompted my post/rant) says, "Each person has a [...] healthy zone of size, diet, and activity in which they function optimally without having to do anything extraordinary to maintain that health." I wanted to jump up and down and scream 'Yes! This!'
Your body's doing the best it can with the tools it has. You can sometimes offer it better tools, but that's not always an option. Punishing yourself - or having others punish you - for 'choices' that you have no control over is ridiculous. If there are ARE choices you can make (the ones that are not dangerous, short-sighted, uninformed, or unpleasant), then give yourself different tools and don't confuse your body by swapping them around constantly.
I hit a point a year or so ago where my activity level dropped to nothing, my food intake shot up with access to new-job money and increased stress, I was coping with a new sleeping schedule, and trying to sort out a new routine. With all of these factors, I offered my body a set of tools that it took and I gained about 25 pounds. Not much, nothing near what others struggle with, but enough that I /felt/ the difference.
It was little things. I panted more going up stairs. I had less energy. I was crankier and even more asocial than usual. Tiny, insignificant things that said, "you are not running on all cylinders" and "there's a bug in the system."
I have a very blase attitude towards food and weight. I am privileged in that I could, in High School and College, eat whatever I wanted to and because of my activity levels, it never adversely affected me. Even when I grew out of 'gawky string-bean' and into 'I have hips!', I basically said, "Fuckit, I love my hips and anyone who tries to make me feel bad about them will get a sock in the nose." I'm lazy as hell, I know it, and I embraced it because I'm Contrary and trying to keep up with the 'ideal' was something my Contrary side fought against. When I started actually feeling physically bad I kind of had to smack myself in the forehead and say, "Well, shit. You can't lean on luck and circumstance anymore." I am thankful that I am employed and able-bodied enough to buy body-friendly food and perform physical activity. I made a lifestyle change towards walking and biking more places and started informing myself about ingredients and quantities of food I was intaking and lost the weight and - more importantly - returned to my happier, not-panting-up-the-stairs self.
I'm physically a very large person, about 200 lbs at my natural weight, and comfortable with that. By BMI standards, I'm fat. I only care because I prefer to be informed; I do not think it applies to me. It's my body, my machine.
Keeping myself within optimum operating parameters is sensible, so that is what I strive to do. My body is chugging along the best she can, and I respect her for her effort. It's not fair of me to blame her when nothing about her weight, shape, or size is actually her fault. She's simply a machine and what I put in is what I get out. If something breaks, I adapt for her sake and mine. She's not a conscious entity out to get me. I must be kind to her, accommodate her and understand her when she does something strange, but as a machine, she can never be inherently bad.
There is so much more to me than just my physical appearance, and I object most strenuously to being defined by it. I object to being defined by any facet of myself, but that's another rant for another time.
Anyway - a diet must be a sustainable lifestyle change if there is any hope of changing the operation and response of my body. Garbage in, garbage out. There is no ideal, shape or weight that anyone else can define for me because statistics can only go so far and - as part of how they are generated - are not tailored to individuals who are magnificent chemical cocktails and masses of moving parts, and any one part might never approach average (or even functioning). I can only attempt to put Non-Garbage in and trying to get Non-Garbage out. On top of physical food and exercise input, mental and situational factors can determine how much Non-Garbage I have to work with. This is obvious to me, especially after my stressful no-job period after college and watching my other stressed-out, unemployed friends gain weight.
The bottom line is that temporary diets are logically fallacious, my body can never be out to get me, and my weight is natural no matter what it ends up or how far from supposed 'correct' it gets.