What explains a lack of self control?

It explain itself.
One is governed too much by emotions and not enough by rational thinking.
An easy way to spin out of control.

Dopaminergic pathway malfunction. Lower response to dopamine, and/or reward pathways. In other words, the system’s rewards are not adequate. Therefore more of X is needed to reach a response. Could also be a satiety problem, no detection of adequate dopamine.

The details in your question sort of belie the question itself. That is, it’s not necessarily “lack of control” that has people doing the things you listed that are “bad for them”. In many cases they’ve made a decision that doing the thing (fatty foods or salty, smoking – sometimes, and other risky behaviors) are worth the risk.

I drive fast on the Interstate. It’s technically illegal to exceed the speed limit by even 1 mph, and I usually push +10 mph. No, I’m not Mario Andretti, but I’m breaking the law – and I’m in good control when I do it. (I don’t weave in and out of traffic, tailgate, speed in bad or crowded road conditions, but I speed when the road is clear and open and it’s otherwise safe to do that.)

I don’t exercise. Is that ‘lack of control’? I’ll grant that it’s laziness. I’m all over laziness. Given my family history of heart disease, it’s probably riskier than it should be. I might regret it one day, but I’m “in control” over whether I do it or not, at least right now.

A lot of people do a great number of things either by ignoring, defying or simply failing to comprehend risks and alternatives. It doesn’t mean that they ‘lack self-control’. Making bad choices (if that’s what it is) isn’t necessarily equivalent to that.

This question is more complex than it initially appears. The reasons why people behave in irresponsible ways are many and varied. Some of those reasons: a lack of maturity which gives rise to an inability to delay gratification; belief systems which elevate selfish human desires above the needs of the ecosystem as a whole; personal characteristics which incline the individual to high risk-taking behaviors; etc.

Stress and negative affect can diminish self-control.

I know for myself, it’s easier to make good, healthy decisions when I don’t have a lot else weighing on me.

Not everyone buys the junk science found in the media so we don’t all agree of what is truly bad for us. So, do your own research and be responsible for what you do and what you eat, etc. Your neighbor will do the same.

“I tell you: one must have chaos within oneself, to give birth to a dancing star”

Friedrich Nietzsche (1844 – 1900)

Potentially helpful: Akrasia

I would say it is the amount of self worth that you have within yourself. If you value yourself alot, then your will power will increase to keep that level of self worth.

Often, a claim of “lack of self control” actually means “you don’t live like I do so therefore you must be wrong!”.

To be sure, there are people who legitimately cannot control themselves, but my take on it is that those who insist on controlling their own lives to the point of denying themselves pleasure or even suppressing their human nature have issues. And those who seek to impose their idea of “self control” on others have control issues and really need to seek professional help for their megalomania.

I drink because it’s fun. I do not drink to excess like an alcoholic, but if I am at home and don’t plan to drive anywhere, I may knock back more alcohol in a night than my wife does in two months (about 3–4 drinks). I eat fatty foods because they taste good. I also am active enough to burn it off, and I stop eating when I am full. (BTW, low-fat foods don’t trigger that feeling of fullness, so you wind up eating more of them, thus negating any benefit. How do you think the Europeans eat so many rich foods and yet we Americans are the ones with epidemics of obesity and heart disease? They eat like I do; full-fat and tasty.)

So am I out of control for having a couple of beers or eating regular (non low-fat) cheese? Am I out of control for being an Agnostic as opposed to joining a strict religion? Am I out of control because I cannot channel my chi like a 5th-Dan Black belt? Some would say I am, but I think the only thing I have a hard time controlling is my irritability.

Very nice answer, @jerv, and very helpful to me, too. It gets right at the social component in ideas of control. Being out of control for society is not necessary being out of control for yourself. Being out of control in others’ opinions is not necessarily being out of control for yourself.

Sometimes, though, we do things that hurt each other emotionally speaking. Is that out of control when you put your good in front of someone elses? What if you really care about them? Where’s the balance?

I am gonna be lazy and just re type my personal philosophy from a different answer as I think its relevant to this question.

I reckon everyones experience if life is different..try as you might you cant ever really understand what its like to be someone else..you are you and they are them. As an example take the fact that many colourblind people often go well into adulthood without knowing that they see cant see colours…in fact we might all percieve colours in different way. At school a teacher holds up a card and tells you that “this is green” thus we attach the label to the shade we see. You could be looking at the same leaf as them and both say that its green but the “green” they see and the green you see might be completely different. If such a basic thing as colour perception could differ drastically from person to person so could all aspects of experiencing reality.

Self control is a sort of label for our reasoning behind our actions and thinking..what seems reasonable to might be completely unreasonable to somone else..i forget now where I am going with this…oh well

not that we shouldnt strive for empathy and understanding as we definatly should.

It’s a measurement or yardstick of our current level of health (physically, emotionally, mentally, spiritually). I would suggest eating healthier food like fruits, vegetable, grain,nuts, seeds.

I came to this conclusion because a drug addict loses self-control.