Sounds obvious right when you see it in front of you, but unfortunately people will que up to offer you unsolicited advice and being able to sieve through the bullshit will save you alot of time and effort.

You see there is a deep seeded physiological reason why so many people like to chime in and tell you why your diet isn’t working etc. You see some people show greater interest in solving your problems than they do their own in a need to prove to themselves that they could deal with your difficulties better than you could ever be expected to showcasing their intelligence and superiority over you.
Consider that if, deep down, inveterate advice-givers view their worth on the basis of how well they compare to others, they must remain in eternal competition with you. One way they can claim interpersonal victory—or gain the relational “upper hand”— is through, authoritatively, providing you with advice.

In plain English, individuals, firmly entrenched in the ego-gratifying habit of telling others what they should do are trying to show superiority over you in an attempt to make themselves feel more important and more worthy despite their obvious low self esteem.
Everyone is quick to offer advice, but be sure to only take it from people you respect and people who are actively chasing their dreams like you.