How do I know when my body is in starvation mode?

your body will not go into stravation mode untill it has to. it takes a lot for it too, people in here band it around too easily. mfp says if you eat to little it may do because they have to cover themselfs for insurance reasons. plus with those amount of calories you are not even coming near to a VLD which could potentially cause your body to preserve.

i base my opionion on academic journals i have read, i also base it on university lectures as well as experience in dealing with weightloss as a PT.

Thats cool: Id suggest most sleep as an overall comment =D. BTW I wasnt suggesting that you had jumped from no training to 7 days a week - I was saying thats how people can enter overtraining mode.

You could consider spreading your meals out more - specifically having breakfast. (Waits for people to scream at me NUTRIENT TIMING ISNT IMPORTANT RAWWRRR) But yeh regardless of whether it affects weight loss, lack of eating is definately linked to negative emotions specifically depression and irritability and as you yourself states that you feel it in the morning perhaps this could help.

your body will not go into stravation mode untill it has to. it takes a lot for it too, people in here band it around too easily. mfp says if you eat to little it may do because they have to cover themselfs for insurance reasons. plus with those amount of calories you are not even coming near to a VLD which could potentially cause your body to preserve.

i base my opionion on academic journals i have read, i also base it on university lectures as well as experience in dealing with weightloss as a PT.

This... when you go into starvation mode, you literally HAVE to be starving... The laws of physics mean that you can't operate without energy. In terms of diet, we call this energy's units calories. If you don't put in calories, your body will use what reserves it has for calories, namely fat. Until this is all used up, your body isn't starving... however by not eating enough food for the other components of food (other than energy) that make it essential, means your body may / will not function 100% as it should. Especially if you're partaking in exercise. "Burning" fat to transfer the energy to do another task such as move, digest food etc requires somne of these nutrients such as water, calcium, iron, electrolytes. So it's not wise to not eat at all and eat a very nutrient rich calorie controlled diet. This includes building block materials such as protein for amino acids which help build/construct tissue/muscle. Likewise, Vitamin C helps with the production of connective tissue such as collagen and also helps build a strong immune system. Zinc helps fight infection, calcium builds strong bonesand helps stop too much fat being absorbed by the intestine when eaten with a main meal. Iron helps keep red blood cells healthy by maximising the oxygen uptake in the cells - which is why anaemic people can feel very tired and lethargic and lacking in "energy".

http://www.myfitnesspal.com/blog/RAFValentina/view/starvation-mode-allelujah-223259

I explained most of it in my blog above.

Use the method in this group: http://www.myfitnesspal.com/topics/show/477666-eating-for-future-you-method

To get a calorie requirement that doesn't require eating back calories, if you want.

The full description is in there, but essentially the website will help work out how many calories you'd need to remain at a certain weight,, taking into account current avg number of hours spent at each activity level.
Since you want to keep losing weight, make your "current" weight on the website what you want to be, and the calories will be adjusted so you can get to that without going under your BMR - going under is what can cause a plateau effect in weight loss.

Starvation mode does not exist. You're body will lower the release of leptin and thus the release of triiodothyronine to slow the metabolism. However this doesn't work for ever as your body can't make energy from nothing. It will thus start eating fat and muscle.

Starvation mode, like toning does NOT exist!

You have done well losing 20lbs already. Great job. Was this a steady loss?
I would try and persevere with the running if you can cope with the weather. Running is great for fat loss. Is there a different swimming pool you can go to? Are evening sessions not possible? Can you do any cardio work at home indoors, skipping rope/ stair climbing? Are you strength training too? Just some ideas!
My thought is..keep eating plenty of the right foods, keep exercising. I wouldn't reduce calories too much on your rest days because even on rest days your body needs fuel to help with the rest/ recovery process.
Good luck with the 40lbs.
As for starvation mode..I would never not eat to lose weight. I'm quite tall and broad and enjoy food. I never go below 1600 cals. If weight loss takes longer then thats fine. I rely on exercise for fat loss more than diet. Having a growling stomach..? Nah!!

Is the question you really want an answer to "how do I prevent my metabolism slowing down"?

...

Naturally as you make major changes to body size there is an expected reduction in maintenance calories you will need to make.

Exactly, well explained, to the T.

My guess is that if your body wants to conserve energy, that you would feel tired, unmotivated and not want to exercise? Otherwise you are fueling your exercise from nothing.

Just going back to the starvation mode bit for a minute, would it not depend on how overweight you are in the 1st place? If you are fairly lean with just a bid of padding and not far off your ideal BMI, I could accept that easier than say if your BMI put you in the obese category and your body had an abundance of fat to burn and enjoy life with.

So my question is, if you are obese and went on a very calorie controlled diet (say 500 to 800 calories a day for a male) why would the body go into starvation mode when there is fat to burn and use up? Serious question, not being a smart *kitten*...

When you are emaciated. The term "starvation mode" gets thrown around loosely. There are many great informative articles on this myth.

Exactly. OP, I'm not blaming you for this, but I get so irritated when I see people casually say "you might be in starvation mode". I've been pretty close to starving, and let me tell you - it was not the scales that informed me, it was the fact that I was in absolute agony. As people have already said, "starvation mode" in MFP terms, means a slowed metabolism. And I wish people would say "slowed metabolism" instead of "starvation".

Again, OP, I am not blaming you for this.

Just going back to the starvation mode bit for a minute, would it not depend on how overweight you are in the 1st place? If you are fairly lean with just a bid of padding and not far off your ideal BMI, I could accept that easier than say if your BMI put you in the obese category and your body had an abundance of fat to burn and enjoy life with.

So my question is, if you are obese and went on a very calorie controlled diet (say 500 to 800 calories a day for a male) why would the body go into starvation mode when there is fat to burn and use up? Serious question, not being a smart *kitten*...

It's true, the amount of body fat you have will dictate how large your deficit can be. But that does not mean you cannot be obese and still enter starvation mode. Consider a few other factors involved:

-Starvation mode is a hormonal response that changes how our body prioritizes energy utilization and storage

-When someone is in starvation mode, the body will reduce energy output as much as possible and increase lipid storage (fat storage)

-Starvation mode usually doesn't occur until someone has been under eating for at least 3 days. Why 3 days? Because that's about how long (minimum) it takes for your body to burn up glycogen stores, it can take longer (and usually does) if the amount being pulled form glycogen stores is small, but it almost never is shorter (this has been tested numerous times in research).

-The very basic calculation for whether someone is going to enter starvation mode is this:

Starvation mode is when the body cannot sustain energetic homeostasis. That means if the calories you consume PLUS the stored energy release rate in the body is less than the calorie needs of the body. Stored energy release rate is classified as how much energy the body can convert from fat the body can mobilize and use at any one time PLUS energy derived from glycogen PLUS energy derived from the conversion of amino acids into ketones. You add stored energy output to the output of calorie intake, look at the concurrency (how much energy is delivered at any one time) and if they don't equal the body's need for energy then you're looking at starvation mode.

Starvation mode will change the way the body releases hormones, which will trigger changes in many body functions (fat storage, energy use, organ output...etc.)

If you think this was complicated, try reading the actual explanation, it's killer, I was a chemistry major in college and it still took me 6 months to figure this stuff out.

Starvation mode is when the body cannot sustain energetic homeostasis. That means if the calories you consume PLUS the stored energy release rate in the body is less than the calorie needs of the body. Stored energy release rate is classified as how much energy the body can convert from fat the body can mobilize and use at any one time PLUS energy derived from glycogen PLUS energy derived from the conversion of amino acids into ketones. You add stored energy output to the output of calorie intake, look at the concurrency (how much energy is delivered at any one time) and if they don't equal the body's need for energy then you're looking at starvation mode.

Starvation mode will change the way the body releases hormones, which will trigger changes in many body functions (fat storage, energy use, organ output...etc.)

If you think this was complicated, try reading the actual explanation, it's killer, I was a chemistry major in college and it still took me 6 months to figure this stuff out.

^also an awesome response.