Your health is like a house, more so than you would realise.
All building construction starts with a solid and structurally sound foundation. Without this, your house is extremely vulnerable to problems. It's safe to say that issues would be a matter of when, not if. In health terms, this is your sleep. Without sleep, all else will fail. You may be able to push through for a short period of time, but your health will suffer for it and it will eventually catch up to you. Research on the impacts of little sleep is very clear (see my sleep article to learn more) and we can now say there is a causal relationship between sleep and Alzheimer's disease, dementia and cancer.
Your walls consist of exercise and nutrition. Both of these help to provide strength, resiliency, structure and protection (immunity). Clearly there are multiple components of exercise and nutrition that can be squeezed inside these walls. The fundamentals are that nutrition and exercise are both useless without sleep. Your performance will drop, injury is more likely and that weight loss you were after, forget it. Nutrition protocols and diets are harder to follow, your brain won't stop craving carbs and simple sugars as an energy booster for the lack of sleep. You won't be bothered to cook and prep your meals.
Everything. Is. So. Much. Harder.
Your roof is your neuro-cognitive health. Your thoughts, feelings, motivations, coping skills, your ability to communicate, your ability to understand and comprehend your thoughts and emotions and then base decisions off them. Almost everything is dictated by not only on how you view yourself and the world, but on the amount of sleep you get, the food you eat and how much you move your body.
If you imagine a cold, miserable, grey, windy and rainy day. It's nice to stay dry and warm inside. If you have a crooked and unstable foundation, leaks in your roof, your walls have holes and cracks in them, you are going to get wet, it'll feel drafty and you'll be cold. If any of these health foundations are compromised, the others will be affected. You can forget about your weight loss goal or that 6-pack you've been wanting if you can't sleep through the night, you can't beat the sugar cravings and you struggle to manage your stress levels.
All aspects of health are multi-factorial. Work on having a solid house of health construction first before making any huge far-reaching goals. You're far more likely to then achieve those goals and sustain them.