Is Fasting The Best Way To Slow Aging?

Autophagy—or cellular cleansing—is usually associated with time-restricted eating. But that doesn't mean it's the most effective way to keep your body young....

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Today’s Health Upgrade

  • Is fasting the best way to slow aging?

  • How fiber protects against cancer

  • Why it’s time to invest in strength

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Fact or Fiction
Is Fasting The Best Way to Increase Autophagy?

If you’ve been looking for ways to fight aging, you’ve probably come across autophagy. It’s your body’s internal cleanup crew, getting rid of cellular junk to replace it with healthier cells, which helps keep your body young and resilient.

While fasting often gets the spotlight for boosting autophagy, research suggests that resistance training is a more effective and sustainable way to stimulate this process. And that’s not all. Instead of fasting, research has found that cutting calories is just as effective as time-restricted eating.

Before you turn your lifestyle upside down, it helps to understand how autophagy works. It’s not a process that can be turned on or off—it’s more like a dimmer switch on a light. Autophagy occurs in your body throughout the day, and certain actions can increase or decrease the level of “cleansing.” 

While fasting can help and is an effective tool, it’s hard to tell how much of an increase is due to not eating or if it’s just because you’re creating a caloric deficit by eating less. 

Either way, if you want to keep your cells young, resistance training and eating fewer calories than you burn are your most reliable anti-aging strategies.

The mechanical stress placed on muscles during resistance training stimulates cellular cleanup, allowing muscles to recover and grow stronger. The result? You’re not only clearing out damaged cells, but you’re also promoting muscle health and longevity.

If you’re worried about longevity, you also want to prevent a decline in mitochondrial function—the powerhouses of our cells. Research suggests that resistance training enhances mitochondrial quality and quantity, giving your body what it needs to keep your cells healthy and help slow aging. 

Nutrition
How Fiber Protects Your Body From Cancer

Dietary fiber has long been known for its digestive benefits, but it does much more than improve gut health. 

Research suggests that adding more fiber to your diet reduces your all-cause mortality risk and decreases the likelihood of cardiovascular diseases and cancer.

Scientists studied nearly 90,000 people to assess the association between diet structure and health outcomes. The goal was to determine how much fiber is needed to significantly reduce these risks, offering insights into the protective effects of fiber beyond gut health.

The researchers found that people who consume the most fiber experience up to a 30 percent reduction in all-cause mortality compared to those who consume the least fiber. Eating at least 25 grams of fiber per day reduces your risk of cancer mortality by 23 percent. Studies even suggest that you can reduce your risk of colorectal cancer by an additional 10 percent for every additional 10 grams of fiber you eat per day. 

Fiber helps lower cholesterol levels, produces short-chain fatty acids that fight against tumors, improves blood sugar control, and reduces inflammation, all of which likely contributed to its protective effect.

The most beneficial fiber comes from whole grains, fruits, and vegetables. Participants who consumed fiber primarily from these foods — and balanced their intake of soluble and insoluble fiber — saw the greatest reduction in health risks. As a goal, aim for 25 to 35 grams of fiber per day. 

Fitness 
Why Strength Is The Best Health Investment

You’re never too old to lift weights, build muscle, and gain strength. New research also suggests that starting earlier can give you a competitive advantage.

Scientists found that the earlier you start strength training, the more it builds resilience and improves health later in life. 

Scientists analyzed what they refer to as strengthspan — or the relationship between strength and longevity, disease, and overall health. They found a direct relationship between strength carrying over from younger ages through different phases of life. 

If you start building strength earlier in life, it increases the likelihood of being a stronger adult. 

When you’re a stronger adult, you’re less likely to suffer from chronic disease, physical decline, neurodegenerative diseases (like dementia), and pain. 

And don’t confuse strength for mass.

While muscle mass is important, the study emphasized that muscle strength is a more critical factor for longevity and health. Maintaining strength provides significant health benefits even in individuals with lower total muscle mass.

If you didn’t start early, there’s no need to be discouraged. As we’ve shared many times before, research suggests you can still build strength and muscle into your 90s! But, whatever age you are now, start including resistance training as part of your routine. The more you invest today, the greater it will pay off tomorrow — and farther down the road. 

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Publisher: Arnold Schwarzenegger

Editors-in-chief: Adam Bornstein and Daniel Ketchell


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