Johns Hopkins cardiologist Dr. Jeffrey Trost shared his weight loss journey and answered questions from followers during a Facebook chat to help others accomplish their health goals.

How do I incorporate exercise into my busy schedule?

I can certainly respect that we all have busy schedules — work, family and life! I can only share with you my experience — I am an interventional cardiologist, have a family with children and I'm on call for the hospital an average of one in every three or four nights per week. In negotiation with my wife, who has been unbelievably supportive, I take one hour every single day — usually after dinner — to go to the gym and exercise. I have known folks who prefer to go early in the morning (before work) and folks who prefer to go after their kids go to bed. I think it is vitally important for you to identify some "me" time to promote your own well-being.

I should also note that some of my colleagues are big fans of using the lunch hour for daily walks; this is a GREAT way to get in 30 to 60 minutes of regular exercise. Incorporating your family in terms of exercise can work, too — a simple walk around the neighborhood or a park is a great way to involve them.

How do you handle cravings?

This is a tough question, and I won't lie: I do get cravings once in a while, like all of us do. What I will tell you is that eating fewer calories — for me — has been as much a mental thing, a state of mind, as it has been a physical challenge. If I tell myself not to think about food, sometimes by focusing on work or something else to distract my feelings, [and] it usually gets me to the next meal.

That being said, snacks are my worst enemy — I try to snack on healthy things, like almonds or fruit — but I always keep track of the calories that I ingest, regardless of when I ingest them.

How important are the timing and size of meals?

I think regular meals at regular intervals are more important than fewer meals at widespread intervals; this has helped me to convince my body that I am full most of the time.

What is considered a ‘healthy size’?

In terms of "healthy size" food, I'd say that it is really important for folks to pay attention to the serving size on food labels (or if eating out, the amount of calories per entree) when determining what a reasonable portion is.

A key part of my success has been to identify serving sizes (i.e., a single serving of cereal), to measure these serving sizes out (i.e., measure a cup of cereal), and not go back for seconds! This also applies to meals that we make at home — many recipes contain serving sizes (i.e., a cup of pasta) and I follow the recommendations very closely.

How do I find the willpower to keep the weight off?

This is an important question. My willpower — my motivation, really — comes from my family. When I was 13 years old, I asked my dad to quit smoking, and, to his credit, he promised me that he would — and he did.

After I walked out of my physician's office a few years ago, frustrated about my continuing weight issue, I thought about my dad and the promise he kept for me. I then thought, What promise can I make to my children? I immediately resolved to lose the weight so that I could have the best opportunity to see my kids grow. I wanted to be a role model to them like my father has been to me.

The keys to my success in maintaining my weight loss have been:

1. I am consistent about what I eat every day, with some variation to keep things interesting. For example, I make my own lunch and generally eat one of two different types of lunch (either a sandwich or vegetarian chili) every single day. This allows me to have consistency in terms of the calories I consume. Same for breakfast.
2. Consistency in counting my calories — it holds me accountable every single day.
3. Consistency in assessing my weight — I weigh myself once a month.
4. Regular exercise, which certainly plays a role in terms of burning calories consistently as well.