However, the important takeaway here is this: The biggest factor in losing muscle is the lack of physical activity, which makes exercise a crucial component when it comes to preventing muscle loss. If you want to figure out the real deal, enter your information into a calculator to learn how many calories you really need for your age and activity level.
If you're a breakfast person, what you eat in the a.m. can set the tone for the rest of your day as far as weight loss goes (whether you're 40 or not!). "A breakfast rich in lean protein, fiber, and plant-based fats is the best option for curbing hunger and cravings later in the day," notes Palinski-Wade. In other words, start off with a breakfast that fits this bill, and you may end up slashing calories throughout the rest of the day.
If you're genetically predisposed to gain weight easily, that may be another strike against you. Even if you don't actually gain weight, you may still gain inches around the waist. This weight gain can be so frustrating, it's easy to become obsessed with losing it, starving yourself or exercising too much or maybe even looking into the latest plastic surgery procedure.
If you eat healthy and exercise regularly and still can’t lose weight, your thyroid might not be working like it should. This happens in about 5% of people, and it's most common in women and people over 60. In addition to weight gain, it can also cause fatigue, joint or muscle pain, and depression. Medications can help, so get it checked if you think it might be an issue.