Why your metabolism changes as you age — and what you can do now

Share Add Us On Google Add as a preferred source on Google ( Aging Untold ) — Metabolism is how your body makes and uses energy, burns fuel, keeps up strength and recovers from day to day. As we get older, that process can change and affect how we feel and how our bodies function. Dr. Rhea Rogers, a board-certified physician, said metabolism is about much more than the number on the scale. Metabolism is the body’s ‘power plant’ “Metabolism really is the language of your cells, and your cells operate on energy,” Rogers said. “What’s supplying that energy is these little battery packs called mitochondria.” Gerontologist “Sam” Cradduck compared metabolism to the body’s “power plant.” Mitochondria are the batteries that power it and every organ has its own power plant, Rogers said. “The brain requires a lot of power, the heart requires a lot of power,” Rogers said. “If you deplete that power in an organ that needs a lot, you’re going to start to see symptoms sooner.” That is why changes in the eyes and ears show up in older people, she said. “They require a lot of power, so that’s why you see the healing start to go and the eyesight start to go quickly,” Rogers said. When cells can’t produce the energy they need, Rogers said, people can notice changes in how they think and feel. “When you cannot produce the energy for all your cells that is needed, you’ll experience things like brain fog or fatigue or just simply being out of it,” Rogers said. She said that energy supports the whole body. “Your heart has to beat. Your brain has to think. You have to breathe. Your immune cells have to fight infection. Everything depends on having energy,” Rogers said. Metabolism is more than weight Cradduck said many people think of metabolism only in terms of weight gain. It also affects how an older person processes medications. “Think of aging as losing energy,” Rogers said. “It’s the cellular energy that’s progressively being lost as you age. That’s why we start to see the symptoms that we associate with aging.” Why strength training matters As people age, they lose muscle and gain fat, a condition called sarcopenia, Rogers said. And many of the hormones people lose with age are tied to maintaining muscle mass. Aging expert Amy O’Rourke said people often turn to weight loss and overlook strength. “What I see happen is people will go on a weight loss thing, and they think they need to lose weight, and they forget that they really need the strength,” O’Rourke said. “So it’s a positive thing to gain weight because it could mean that your muscles are getting stronger.” O’Rourke recommended strength training two to three times a week as people get older. “To the younger people out there, I’d say start strength training now, so that you don’t have such a cascading effect when you get older,” O’Rourke said. How muscle connects to glucose Rogers explained that muscle plays a role in how the body uses glucose. She said glucose provides energy and has to be taken up by muscles to be used for energy. “Insulin resistance is when your muscles will not take that glucose up, And that’s where prediabetes and all that starts, at the level of the muscle. So the more muscle that you can build, the better you can help that process,” Rogers said. Type 2 diabetes is showing up earlier, Rogers said, and cited metabolic inflexibility, which she described as the inability to go back and forth between using fat for energy and using carbs for energy. Your cells should be able to go back and forth. “That makes you very efficient, and we’re losing that efficiency because of things like toxins, inflammation,” Rogers said. Building health instead of waiting to manage disease Aging well coach Katherine Ambrose said the focus can be on creating health and energy rather than waiting to manage disease. Rogers listed muscle stimulation, inflammation control, toxin removal, good nutrition and good sleep. Key takeaways Metabolism is about energy, not just weight. Every cell runs on energy, including the heart, brain, lungs and immune cells. Muscle is a primary metabolic driver. Losing muscle mass as you age is one thing that can slow metabolism. Aging is the slow loss of cellular energy. When mitochondria slow down, your overall vitality drops. Life is about function, not weight. A healthy metabolism gives you the physical strength to stay capable. This program is provided for educational and informational purposes only and does not constitute providing medical advice or professional services. The information provided should not be used for diagnosing or treating a health problem or disease, and those seeking personal medical advice should consult with a licensed physician. Always seek the advice of your doctor or other qualified health provider regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have seen on this program. If you think you may have a medical emergency, call 911 or go to the nearest emergency room immediately. No physician-patient relationship is created by this program or its use. Aging Untold/Gray Media, nor its employees, contractors or agents, nor any contributor to this program, makes any representations, express or implied, with respect to the information provided herein or to its use. Copyright 2026 Gray Media Group, Inc. All Rights Reserved.