This is actually a little more nuanced than most understand. While we all are still subject to death, debilitation and disease do not need to be a large consequence of this. I realize many will be taken aback by this initially, but it is true,
First, consider Moses. Deuteronomy 34:7...And Moses was an hundred and twenty years when he died: his eye was not dim, nor his natural force abated...
Second, those who live according to biblical guidelines "generally" live healthier lifestyles. Vices generally tend to take years off a person's life expectancy and lend themselves to disease.
Third, one of God's means of correction is to afflict His children in a variety of ways; sickness and death amongst them. So if the "health" gospel is tied to holiness, there is an avenue for less frequent incidences of the need for correction, and possibly better health.
And finally, God actually tells us that He will heal us in the book of Isaiah. Most people will cite Isaiah 53 to back such a claim. I believe that primarily deals with spiritual healing and reconciliation with God. But in chapter 58 I believe God is actually speaking about physical healing for those who actually live according to the commandments as He actually intends them.
The chapter begins by God taking exception to His people's transgression because they seem to be observing His commandments, but are not. He does so by using the example of fasting. He tells them what true of them and then contrasts this with what He actually desires. Then, in verse 8, He tells them what will occur if they actually do as He desires. One of those things is that their health will spring forth speedily. This doesn't mean God is excluding any aspect of health, but it certainly would include physical health.
I'm not a name it and claim it guy, but there are great benefits from learning God's ways and living accordingly; both here and in the age to come.