Carbs vs. Fats: Which is Better for Health and Longevity?

When it comes to optimizing health and longevity, the debate between fats vs. carbs: which is better for health and longevity, often takes center stage. For those embracing keto, carnivore, or animal-based diets, this discussion becomes even more relevant. Let’s explore why fat trumps carbs as a sustainable energy source, delve into the best carbs and fats to consume, and provide meal plan ideas to support a thriving, nutrient-rich lifestyle.

Understanding the Role of Macronutrients

Protein provides essential amino acids—the building blocks for muscles, hormones, and enzymes. While protein is vital for the body, it’s carbohydrates and fats that are primarily used for energy. So, when considering carbs vs. fats, the choice between the two often comes down to sustainability and long-term health benefits.

Carbs as Fuel

Carbohydrates are broken down into glucose, a quick energy source stored in the liver and muscles as glycogen. While carbs can fuel high-intensity activities, their energy supply is short-lived. Once glycogen stores are depleted, the body requires more frequent food intake, potentially leading to blood sugar fluctuations, cravings, and reliance on carbohydrate-rich foods. Carbs vs. fats can influence energy consistency, as carbs often lead to energy crashes, whereas fats provide more stable energy over time. Excess glucose that cannot be stored as glycogen is converted into fat, which can contribute to weight gain if carbohydrate intake consistently exceeds energy needs.

Fats as Fuel

Fats are metabolized into ketones, a stable and efficient energy source. Unlike carbs, fats provide sustained energy without the spikes and crashes associated with blood sugar. In the ongoing carbs vs. fats debate, fats come out on top for those looking for steady energy throughout the day, helping improve metabolic flexibility and reduce the risk of chronic diseases.

Dr. Eric Westman explains, “The human body wasn’t designed to consume a constant stream of carbohydrates. It thrives on fat as its primary fuel in a ketogenic state.”

Why Prioritize Fats on Keto?

1. Fats Fuel Ketosis:
   Fats are the cornerstone of ketogenic and carnivore diets. By prioritizing fats over carbs, you can encourage your body to enter ketosis, a metabolic state where it burns stored fat for energy instead of glucose. This shift leads to improved metabolic health, reduced inflammation, and enhanced brain function.
2. Nutritional Powerhouse:
   High-quality fats provide essential fatty acids that the body cannot produce on its own. They also enhance the absorption of fat-soluble vitamins like A, D, E, and K, ensuring your body gets the nutrients it needs to function optimally.

The Health Benefits of Fat Over Carbs

Choosing fats over carbs as a primary fuel source supports overall health and longevity in several ways:

1. Reduced Inflammation:
   Chronic inflammation is associated with high carbohydrate consumption, particularly from refined sugars and grains. In contrast, omega-3 fatty acids, found in sources like fatty fish and pastured meats, exhibit anti-inflammatory effects. Research highlights how reducing dietary carbs and increasing fats can significantly lower inflammatory markers like C-reactive protein (CRP) .
2. Improved Insulin Sensitivity:
   Unlike carbohydrates, which cause spikes and drops in blood sugar levels, fats provide a consistent and steady source of energy. Research shows that reducing carbohydrate intake improves insulin sensitivity—a key factor in preventing Type 2 diabetes. For instance, the ketogenic diet has been shown to lower hemoglobin A1c levels, a marker used to evaluate long-term blood sugar control.
3. Brain Health:
   Ketones, which are produced when the body burns fat for energy, act as a clean and efficient fuel source for the brain. Research has linked ketones to enhanced cognitive performance, neuroprotection, and potential benefits in neurodegenerative conditions like Alzheimer’s disease. A study published in Frontiers in Aging Neuroscience found that ketogenic interventions improved memory and focus in older adults.
4. Support for Longevity:
   Relying on fats for energy minimizes oxidative stress, a major contributor to cellular damage and aging. By reducing oxidative stress, fats help protect cells and promote repair. Additionally, the metabolism of fats through a ketogenic diet supports mitochondrial function, which is essential for healthy aging. Ketones, produced during fat metabolism, activate important repair processes such as autophagy (cellular cleanup) and help lower reactive oxygen species (ROS), which are harmful molecules that accelerate aging. Together, these mechanisms enhance longevity by improving cellular health and reducing the risk of age-related conditions.

Scientific Insights in Practice

Dr. Eric Westman, a renowned keto expert, emphasizes that fats provide sustainable energy without the blood sugar crashes associated with carbs. Similarly, Dr. Annette Bosworth (Dr. Boz) highlights that fat intake supports hormonal health and reduces the risk of chronic diseases like heart disease and Type 2 diabetes.

The Best Carbs to Eat on a Low-Carb or Keto Lifestyle

While carbs are limited in keto and carnivore diets, strategic inclusion of nutrient-dense options can be beneficial:

• Low-Oxalate Vegetables: Opt for zucchini, cucumbers, and cauliflower to keep oxalate levels low and carbs minimal.
• Berries: Blueberries and raspberries provide antioxidants and are low in sugar when eaten in moderation.
• Squash: Spaghetti squash and pumpkin are excellent occasional carb sources.
• Fermented Foods: Kimchi and sauerkraut support gut health while keeping carb content low.

The Best Fats for Keto and Carnivore Diets

Not all fats are created equal. Prioritize these high-quality fats:

• Animal Fats: Tallow, lard, and duck fat are nutrient-rich and perfect for cooking.
• Butter and Ghee: Both are excellent sources of fat-soluble vitamins and enhance flavor.
• Coconut Oil and MCT Oil: Quick to metabolize into ketones, these are ideal for energy boosts.
• Egg Yolks: Packed with choline and healthy fats, egg yolks are a staple in low-carb lifestyles.
• Fatty Fish: Salmon, mackerel, and sardines are high in omega-3 fatty acids for heart and brain health.

Avoid seed oils such as canola, soybean, and sunflower oil due to their inflammatory nature and high omega-6 content.

How to Include Carbs on a Keto or Carnivore Diet

For those who want to incorporate carbs strategically:

1. Cycling Carbs: Some people find benefits in periodic carb cycling, especially if they are highly active or seeking muscle gains.
2. Seasonal Eating: Consume low-carb fruits and vegetables that align with ancestral eating patterns, such as squash in fall or berries in summer.

Sample Meal Plans for Health and Longevity

Below are meal ideas to help you incorporate the best fats and carbs into your diet while prioritizing protein:

Keto Plan

• Breakfast: Scrambled eggs with grass-fed butter, avocado slices, and coffee with MCT oil.
• Lunch: Grilled chicken thighs with roasted cauliflower and a drizzle of olive oil.
• Dinner: Ribeye steak with a side of sautéed asparagus and tomatoes in tallow.

Carnivore Plan

• Breakfast: Fried eggs cooked in ghee with a side of beef bacon.
• Lunch: Pan-seared salmon with melted butter.
• Dinner: Lamb chops with bone broth as a side beverage.

Why Fats Are the Better Choice for Longevity

The ability of the body to efficiently store fat and convert it to energy during periods of fasting or calorie restriction is key to longevity. While carbs provide immediate energy, fats promote metabolic flexibility, reducing the wear and tear on the body caused by constant spikes in blood sugar and insulin levels. This highlights why, when considering carbs vs. fats, fats are the better choice for long-term health and longevity.

Dr. Eric Westman and Dr. Annette Bosworth often highlight the benefits of fat-adaptation and how it aligns with our ancestral eating patterns. They emphasize that fats not only support energy needs but also enhance cellular repair processes vital for a long life.

Final Thoughts on Carbs vs. Fats

When prioritizing health and longevity, fats are the clear winner over carbs for energy and disease prevention. By consuming high-quality fats and limiting carbohydrate intake to nutrient-dense options, individuals on keto, carnivore, or animal-based diets can enjoy stable energy levels, improved metabolic health, and a path toward a longer, healthier life.

For more insights on how a ketogenic lifestyle promotes longevity, check out our previous blog, How Keto Can Help You Live Longer: The Science Behind Longevity.