Many people skimp on these things because they’re so busy doing work or other supposedly important things. This strategy is only good in the very short-term, like when you’re eager to finish up some exciting project. However if, on a regular or even semi-regular basis, you aren’t getting enough sleep, are eating crap, aren’t moving very much, or not seeing those close to you, you’re wasting time. Simply put, your body and mind are considerably less efficient when you’re not treating them well. How productive will you be when you’re tired every day? Obvious not very much. The consequences are apparent in the short term time of days.
The long term impact is even more striking. By not living vitally, you also trade your future health for extra time now. Surely you’d cut off years from your life in a strict sense. But it’s even worse that because you’re also cutting off productive and enjoyable years from your life because you’re busy treating health problems in the latter part of your life.