If you had any real liver problems I think you would know about it! Its not something you can avoid.
Having said that, people's livers function at different levels. Some have excellent liver function and some have slightly lower liver function that is still within the 'normal' range. The great thing about the liver, however, is that it is an incredibly resilient organ and with a bit of TLC you can get yourself into top working condition.
Below I will outline a few bits of advice for looking after your liver. HOWEVER, you should not carry these things out because 'you are scared you have damaged your liver and you want to heal it'. By doing that you will be perpetuating a fear. Attaining tip-top physical condition is a great aspiration, but it should never be done at the cost of your psychological health.
The liver is the first line of defence against screening toxins from the bloodstream. Therefore, it is all about what you put in your body. If you overfeed your body chemicals, alcohol or sugary, fried, processed or (unhealthy) fatty foods, the liver is going to suffer as it will need to work harder to screen these things out before they get into circulation. That is not to say that you can't have these things - a good working liver will do well to screen them out. But the best working livers are the ones that don't really have to!
Moreover, there a supplements you can take that have a positive impact on the liver. I am wracking my brain right now to come up with a list but the only one I can think of is Milk Thistle. The active ingredient in Milk Thistle (or the one we want for these purposes) is Silymarin. The action of Silymarin is to protect liver cells from damage and to also aid in their actual regeneration.
Often Milk Thistle will come mixed with other ingredients such as dandelion and artichoke heart. These do things such as increase bile production (my memory is still faltering here) which assists in regulation of the liver.
Other than that, try to avoid environmental toxins such as those put in our foods (a big one! - eat organic) and other pollutants. Moreover, as with EVERYTHING in the human body, stress is toxic and will need to be avoided (or minimised) as best as possible.
The liver does not function in isolation. It is part of a large overall system that is the human organism. You need to look after all your bits and pieces to really gain excellent health and wellbeing. The means feeding the body, mind and soul healthful things whilst also avoiding unhealthy inputs.
There's nothing better than a fresh, crisp day in the middle of spring when you have a bounce in your step and an enthusiasm about the world around you because you've taken steps to ensure your body is working the best it can be!