Yes and no.
Free speech laws and rights allow you to legally criticize. However, you shouldn't do that to everyday people because they either already know what they're doing is harming themselves or they don't care and your criticism is only going to make them more stubborn and resistant to change. Either way, you're not helping.
On the other hand, as a society we should encourage and incentivize good and healthy behavior. We should be making things that are good for you more available and more affordable (e.g., government subsidizing fruit and vegetable growers so they can be sold at cheap prices). At the same time things that are unquestionably bad for your health should be expensive or otherwise difficult to get by making them difficult to sell through various restrictions on when, where, etc., they can be obtained or used.
My reasoning for the restrictions make sense even if you believe very strongly in personal freedoms and a no-government, no-regulation world. The spoken or unspoken agreement of living in a society of rules and laws is that there are going to be some imposed limits on your activities for the greater good. Legally, you have to have a license to drive, can't drive while intoxicated, etc. As part of the above understanding, it's near universally considered okay to interfere in someone's life if they are causing harm to others (because it serves the greater good). Almost to the same degree (some people make a distinction) if they're causing harm to themselves. What is considered too harmful, harmful enough to warrant intervention, is debatable, but the general idea is, I think, undisputed. Now, you may think that self-harm is a personal choice, but since in most places in the world the society/government is responsible for providing health care in one way or another. An unhealthy person anywhere means the society at large uses time/resources to treat them. If we had unlimited resources things might be different, but we don't. When it's for something that could be avoided (binge drinkers needing their stomachs pumped, etc.) we as the society are paying for their recovery when we could be paying less for the prevention instead and using our resources for something else. So we, as a society, have reasons to cross someone's body autonomy line depending on the circumstances.
I think the only real question (unless you're one of those people who think it's okay to let someone die when you have the means to save them) is how strongly you want to enforce things. Outright banning personal choices that are harmful to health doesn't work (for the reason at the top of this post) but providing people with information about what their choices' consequences are (i.e., educating) and making alternatives available is a really good idea.
Basically, you make the healthy choice the easier choice and more people will choose it.