smooth health bar animation

[Capadillo]

I'm attempting to create a smooth health bar animation for a personal project. The goal is to eventually make it as smooth as possible, smoothing over the jumps when you do get health back. If that makes sense. Here is what I have at the moment:

function Animate_SetWidth(self, changeWidthTo)
    -- Make sure we have a timeline & animation.
    if ( not self.animation ) then
        self.timeline  = ANIMATION_MANAGER:CreateTimeline();
        self.animation = self.timeline:InsertAnimation(ANIMATION_SIZE, self);
    end
    local width = self:GetWidth();
    local height = self:GetHeight();
    self.animation:SetStartAndEndWidth(width, changeWidthTo)
    self.animation:SetStartAndEndHeight(height, height)
    self.animation:SetDuration(500)
    self.animation:SetEasingFunction(ZO_EaseOutQuadratic)
    
    self.timeline:PlayFromStart()
end

So that brings me to my questions:

1. Is this the best way to achieve what I want?
2. And is there a way to stop it from the start-stop animation when regaining health/magicka/stamina?

EDIT: Changing the duration to 2 seconds makes it a little less jerky but makes it seem much slower.

EDIT2: Is possible to animate a statusbar rather then creating a blank control and adding on a backdrop?