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Diet & Nutrition

5 Ways to Boost Your Metabolism After 40

Strategies from a visionary nutrition expert to jumpstart your system.

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Q: After I turned 40, it felt like my metabolism and energy slowed a lot, and I developed more digestive issues, food allergies, and psoriasis. The pounds started to creep on, even though I was eating the exact same food. Now that I’m closer to 50, I’ve developed a belly bulge or “menopot.” Plus, key heart-disease risk factors, such as blood pressure and blood sugar levels, are going in unhealthy directions. I tried the Paleo diet and then the ketogenic diet, and neither one worked for me. Is it just normal to have all these different health issues develop and worsen as we age?

—Karen M., Cape May, N.J.

Source: Radical Metabolism: A Powerful New Plan to Blast Fat and Reignite Your Energy in Just 21 Days by Ann Louise Gittleman, PhD, CNS

A: The short answer is no. The health issues you describe are typically seen in people over 40, but they don’t have to be. Over time, many people develop a toxic metabolism, and when this occurs, wide-ranging health issues can develop and worsen. Even beneficial diets might not work if your metabolism has turned toxic. Trailblazing nutritionist Ann Louise Gittleman, PhD, CNS, observed that this phenomenon has become so common that she wrote a new book, Radical Metabolism, which delves into how to rescue a stalled metabolism that typically occurs after 40.

A Toxic Metabolism

Metabolism means transforming the food you eat into energy via countless life-sustaining chemical reactions that mostly occur at the cellular level. Our metabolism controls digestion, as well as getting nutrients into the cell and waste products out.

Sometimes, our cells aren’t getting the nutrients they need, aren’t detoxifying well, or both. “Because so many toxins are in our food, water, and air today, toxins progressively accumulate, and the body has a difficult time cleaning them all out,” says Gittleman. “When this happens, metabolism becomes toxic and sluggish, and your ability to control weight and maintain healthy function in organs and systems throughout the body deteriorates.”

5 Rules to Boost Metabolism

To boost your metabolism so that it keeps you lean, healthy, and energized as you get older, try these rules from Radical Metabolism:

1. Change the Fats in Your Diet

To shift your body from sugar-burning mode into fat-burning mode, eat less sugar, and don’t skimp on fats. Cell membranes are made of fat, and to strengthen cell membranes and counter resistance to many different hormones, including insulin, it’s important not to lower fat intake, Gittleman says. Instead, change the fats in your diet.

Eliminate high omega-6 refined vegetable oils (corn, soybean, cottonseed), trans-fats (partially hydrogenated oils found in margarine and butter substitutes), and very-long-chain fatty acids (canola oil, peanut oil, whole peanuts, peanut butter, mustard oil, and borage oil). Instead, eat whole olives and olive oil; avocados and avocado oil; coconut oil; grass-pastured animal products and wild cold-water fish; nuts (organic almonds, Brazil nuts, pistachios, hazelnuts, and pine nuts); seeds (hemp seeds, chia, sunflower, safflower, sesame, flax, pumpkin seeds); and cold-pressed seed oils.

Did You Know?

Whole olives and high-quality olive oil are great sources of metabolism-boosting healthy fats.

If you’re stuck in your weight loss efforts, consider adding hemp seeds and hemp oil to your diet, and possibly a gamma-linolenic acid (GLA) supplement, such as black currant oil. GLA is unparalleled in promoting fat burning by activating a type of fat called brown fat, according to Gittleman.

2. Incorporate More Bitter Foods in Your Diet

Many individuals have difficulty digesting and metabolizing fats. If you have this problem, then simply eating more healthy fats and less sugar is not going to result in the metabolic shift needed for weight loss and optimal health—and popular higher-fat diets such as Paleo or ketogenic diets may not work for you. To optimize your body’s ability to use healthy fats for your benefit, it’s important to help support the liver to produce adequate, healthy bile. Bile helps your body break down all the fats you eat, which is critical to healthy membranes and healthy hormones. Bile also helps remove toxins so they can be flushed out of your liver. Adequate, healthy bile promotes healthy function of the gallbladder, the organ where bile is stored.

The top strategy to support the production of adequate, healthy bile is to incorporate more bitter foods in your diet, including asparagus, dandelion greens, collards, radicchio, red leaf lettuce, watercress, arugula, broccoli, cabbage, endive, artichoke, cauliflower, kale, Swiss chard, and even coffee and cacao. You could also try an herbal bitters formula. Popular ingredients include barberry bark, dandelion, fennel, gentian root, globe artichoke, milk thistle, wormwood, and yellow dock.

3. Rebuild Your Muscles

Fat gain always accompanies muscle loss, so addressing age-related muscle loss, known as sarcopenia, is another important step in restoring healthy metabolism. To get the essential amino acids your body needs, eat protein daily. But don’t overdo it: The body can utilize only 4–6 ounces of protein at a time, Gittleman says. Also make sure the protein you eat is high- quality. Avoid processed meat products from factory-farmed animals, and instead focus on wild-caught fish and organic and pasture-raised meat, eggs, and dairy.

4. Repair Your Gut

Healthy digestion is key to a robust metabolism, but many people suffer from unhealthy bacterial balance, as well as permeable or “leaky” gut, due to exposure to toxins and allergens. To restore gut health, Gittleman recommends:

  • Avoiding sugars and allergenic foods (such as gluten, dairy, and eggs)
  • Avoiding refined carbs, processed fats, and factory-farmed meats
  • Repopulating your gut with beneficial bacteria by eating more naturally fermented foods, such as sauerkraut and kimchi, and/or by taking probiotic supplements

5. Reduce Your Toxic Load

We’re exposed to toxins that run the gamut from hormone-disrupting chemicals (known as obesogens), which show up in tap water, nonorganic foods, and nonstick cookware, to dangerous pesticides such as glyphosate, which is sprayed on genetically modified corn, soy, sugar, and canola. If the body has a heavy toxic burden, many of its resources are needed just to keep the poisons cleared out, leaving precious few available for fat burning.

To jumpstart your metabolism, you may need a radical lifestyle cleanup. Opt for organic real foods whenever possible. Ditch artificial air “fresheners.” Invest in an air purifier. And improve your body’s detoxification processes by drinking plenty of fresh water, as well as by sweating (a form of detoxification through your skin) by taking infrared saunas or exercising.

Is Your Metabolism Under Toxic Stress?

Think you might be suffering from a toxic metabolism? Here are some of the most common signs:

  • Metabolism seems to have slowed since turning 40
  • Type 2 diabetes or prediabetes diagnosis
  • Suboptimal lipid profile (higher LDL and triglycerides, lower HDL)
  • Elevated blood pressure
  • Experiencing “menopot” before actual menopause: increased belly fat, higher waist-to-hip ratio
  • Craving snacks, such as coffee or candy, throughout the day
  • Food allergies or intolerances to gluten and dairy
  • History of gallstones or gallbladder surgery
  • GI discomfort after eating fatty foods
  • Constipation
  • Nausea, heartburn, gas, bloating, or other digestive symptoms

Source: Radical Metabolism: A Powerful New Plan to Blast Fat and Reignite Your Energy in Just 21 Days by Ann Louise Gittleman, PhD, CNS