Not necessarily.
I have had a weight problem my whole life. My best weight ever was 205 lbs at 6’ and 22 years old.
I got to there at 1000-1200 calories a day, and 10 grams of fat. I was also, and have always been active, until my back crapped out.
I looked good but was still a big guy, and I was miserable.
As the years have gone by I have gained weight, but it’s not been from over eating. I seldom eat more than one meal a day, and it’s normal portioning.
I do not snack all day, and do not binge eat, but I never drop away from the 250-270 level.
Obesity is not an easy fix, and is not always about the persons habits.
You may be interested in reading “The Fat Switch”. One of our children has weight troubles, even though she is very active. Weight gain/loss is tied to our body’s ability to read the hormone leptin. Loosely following what the book recommends caused our daughter’s “fat switch” to turn off and she slimmed down quite a bit.
FWIW, the time in my life when I struggled with weight was when I thought low fat/diet foods would keep me slim. Had the opposite effect. Started eating real food, including full fat dairy, and I easily slimmed down to normal. We’ve been fed lies about what constitutes a healthy diet.
I’m 6’1”, 210, still losing. Gained a lot of weight after quitting smoking. 38” waist.
I walk about an hour, brisk pace and drink lots of water. Lots of fruit, meat and vegetables. NordicTrak bike in cold weather. Going to quit at 199 lbs, 36” after trading fat for muscle.
Find what works for you and go for it. You’ll feel better. You can do it if you want it.
Look for articles on ‘gut flora and weight control’. Current thinking is that the mix of bacteria living in your gut can determine your body mass. The fact that you eat properly but cannot lose weight is classic sign that this might be what you are dealing with.
http://www.scientificamerican.com/article/how-gut-bacteria-help-make-us-fat-and-thin/