Here are a few common culprits you might be over doing:
Nuts are a great source of healthy fats but they are quite high in calories. A serving of nuts is only about 8-10 nuts which probably just seems like a tease. Try having nuts as part of a snack with a piece of fruit or on top of a salad or cereal instead of just on their own. You will be less likely to over indulge but still get the benefit of the healthy fats and wonderful flavour!
2) Smoothies
They're quick, they're easy and they are even easier to over do. While you can pack a lot of nutrition into a smoothie you can also just pack a lot of stuff into them. This can lead to a lot more calories and a lot more sugar than you bargained for. Think of it this way, if you would find it excessive to eat all the individual fruits and items you put into the smoothie before you blend them up, you are probably packing in too much.
A couple of tips to trim things down: try putting in one vegetable for every fruit. Cucumbers and spinach are great additions. Also try to avoid adding extra sugar. The fruit is sweet enough. There is no need for extra juice, honey or sweetened yogurt. Finally add in some protein and fiber to make it more filling so you won't go over board. Protein could include nut butter, protein powder or Greek yogurt. Extra fiber might include flax seeds or oat bran. Experiment with what works best for you!
3) Protein Shakes
Most people over do their protein in a day. Unless you eat little to no meat, body build or do extreme aerobics like long distance running, you probably don't need these shakes. Focus on getting proteins in your meals and snacks through meat, low fat cheese, eggs, beans, tofu and nuts.
4) Greens
I'm talking about bottled greens. While they can provide a source of vitamins, you are better off eating ACTUAL greens than using these products.
5) Olive Oil
Also a healthy fat, but too much of a good thing is still too much of a good thing. Avoid over doing oils on salads or when you are cooking. Make a little go a long way and your will avoid accidentally increasing your calories too much.
6) Diet Cookies/Treats
Sure its a little lower in calories but a cookie is a cookie is a cookie. Sure it has no added sugar but it also likely doesn't fill you up or provide any real nutrition. If you need a sweet fix, these treats can prevent you for over doing it, but don't take these lower calorie alternatives for granted because they can still add up.
7) Juice
We often neglects what we drink and juice has such a healthy image about it we often don't factor in how much sugar it really provides. A measuring cup of juice has as much sugar as 5 packets of sugar. Think about this the next time you chug down a big glass.
All of these items can fit into a healthy well balanced diet. Just be aware that just because something is healthy does not mean you can go nuts with the amount you have.