To jumpstart your weight loss, the biggest focus should be to develop habits that will help you build or maintain your muscle mass. "The most effective way that women over 40 can boost their metabolism is by building muscle through weight-lifting and resistance training," says Dr. Peterson (more on that to come). But nutrition and sleep habits also play a role here.
For a sustainable plan, "I don't like to hyperfocus on calories. It's important to have a high-quality diet of lean protein, whole grains, and fruits and vegetables," Dr. Stanford says. "Processed foods lead to weight gain, so the less processed the food you eat, the better." And the more satisfied you could end up being. Her example: A nice meal of salmon plus some grains and a vegetable and a salad can give you a lot more volume than a Shake Shack stop would, and would give you more of a sense of being full afterward. When it comes to the high-quality diet she advocates, "nothing is bizarre—we know that lean protein, whole grains, fruits, and vegetables are constant no matter how the guidelines for healthy eating have changed over the years," she says.
Oxidative stress occurs when the balance between free radicals in the body and our ability to fight against them is uneven, with free radicals prevailing. Free radicals can cause disease and there is an association with an increased risk of formation of free radicals as we age. That's why after a certain age, building up our defenses (through having lots of antioxidants in plants) can help reduce this imbalance and stack the cards in our defense system instead.
2. Exercise More. Contrary to what your body may want to do, you must exercise more regularly as you age, not less!  If you’re finding yourself slowing down, gradually start ramping it back up.  It’s not a good idea to go from taking an occasional walk to running a 10K.  That’s a fast track to getting an injury.  But start finding ways to fit more physical activity to your life.  The more you exercise, the more insulin sensitive you become (that’s the opposite of insulin resistant!)
Exercise can actually increase your energy. Just three hours of exercise weekly can improve the health of menopausal women.35,36,37,38,39 You may be able to add aerobic exercise into your everyday life without even noticing it! Take a walk during lunch with your colleagues. Go for a bike ride with your family after dinner. Put some music on while cleaning the house and add some dance moves. Jump on an elliptical trainer or treadmill instead of sitting while watching your favorite show.
Sleeping enough is important, and if your lifestyle is making you cheat sleep, then think about what you can do to get enough. Sometimes, however, biology is keeping you from enough shuteye, and it's imperative to solve that. "Untreated obstructive sleep apnea can lead to additional weight gain," says Dr. Stanford. If you are making all the right efforts to get restorative sleep and still don't feel restored, consider seeing a sleep doctor, who can drill down on the problem and help you find some solutions.
Your body has to work harder (meaning it burns more calories) digesting protein than it does fat or carbs, so Palinski-Wade recommends the strategy of upping protein intake to many of her clients, including women who are 40 and over. "Although I don’t promote very high-protein diets, increasing your protein intake from 15 percent of your total calories to 30 percent can help you boost the calories your body burns during digestion, which may just help speed weight loss."
Starting in your 30s, you can lose three to five percent of your muscle mass each decade if you don’t stay active. Note the last part of that point: “If you don’t stay active.” As you get older, "there's a lot of competition for your time and energy," says Dr. Yancy. For some men, that can push exercise out of the picture. But it doesn't take heroic efforts to put it back into your life.
Dina - WOW!! This is awesome news to hear! Just know that you are not alone in trying to be healthy after 40 or even after 50! You couldn't have said it better though when you said to maintain a better diet and exercise routine SLOWLY! I always tell my clients that it is a healthy lifestyle that you are looking towards living. In my mind there are no such things as quick fixes and to make these changes over time will lead to the overall lifestyle you are looking for. Congratulations to you and continue to make those slow consistent changes to your health! YES U CAN!

What does that mean for you? That the weight loss process naturally becomes harder as you get older...that's just a fact and accepting it means you can stop punishing yourself or feeling ashamed about your body. Instead of focusing on the negative, focus on the things you can control: Your workouts, activity levels, diet, stress management, sleep management and, most important, your attitude.
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