A Forgotten Science That Explains Why Most People Get Weight Loss Wrong
Would it surprise you to learn that losing weight is less about calories and more about a hormone called insulin?
Would it surprise you to learn that the way you eat to improve blood sugar is not the same way you eat to maximize fat loss?
And would it surprise you to learn that most people answer the following question incorrectly?
A Question Almost Everyone Gets Wrong
One of these snacks is better for fat loss, and the other is better for blood sugar stability.
Which one better supports fat burning?
-
- Apple + Peanut Butter
- Apple + Non-Fat Greek Yogurt
Take a moment before answering.
Most people confidently choose apples with peanut butter, believing that adding fat to carbohydrates slows sugar and supports weight loss.
That answer feels logical.
It’s also wrong when the goal is fat loss.
The correct answer is apple paired with protein, in this case, non-fat Greek yogurt.
Why This Feels So Backward
For decades, nutrition advice has focused on:
-
- Calories
- Sugar
- Glycemic index
- Glycemic load
These tools help explain blood sugar, but they do not fully explain fat loss.
In focusing so much on sugar, we missed something more important:
how the body decides whether to burn fat or store it.
That answer was published more than 60 years ago.
The Science That Explains It All (Published in April 1963)
In April of 1963, scientist Philip Randle published research explaining how the body switches between burning glucose and fat. ¹
This research, now known as the Randle Cycle, also called the glucose–fatty acid cycle, showed that:
-
- When glucose is being burned, fat burning is reduced
- When fat is being burned, glucose use is reduced
- The body prefers to burn one primary fuel at a time
This was not a theory.
It was basic human physiology. ¹²
The Two Main Fuels Your Body Uses
Your body runs mainly on:
-
- Glucose, from carbohydrates
- Fatty acids, from dietary fat or stored body fat
Your body always uses some of both, but one fuel is dominant at any given time. ¹⁰
Which fuel dominates depends on:
-
- What you eat
- How foods are paired
- Insulin levels
- How quickly does insulin come back down
The ability to switch between fuels is known as metabolic flexibility. ¹¹
What Is Insulin and Why Does It Matter
Insulin is a hormone released by the pancreas. Its role is to regulate how energy is used within the body. ³
Insulin signals cells to:
-
- Use glucose for fuel
- Store excess energy
- Temporarily pause fat burning
Insulin is not bad.
It is essential.
The problem arises when insulin remains elevated too often or for too long, preventing fat burning from returning. ⁶ ⁷
A Simple Lab Example That Explains Insulin
Metabolic researcher Ben Bikman often shares a powerful lab-based example grounded in adipocyte research (adipocytes are fat cells).
In laboratories, fat cells can sit in a Petri dish with:
-
- Glucose
- Fatty acids
- Amino acids
- Calories
And nothing happens.
But when insulin is added:
-
- Fat cells pull in glucose
- Fat cells pull in fatty acids
- Fat storage turns on
- Fat breakdown turns off
The fat cells grow. ⁴ ⁵
This reveals a key truth:
Calories alone do not tell fat cells to store fat.
Insulin provides the instruction.
The Glucose-Focused Phase (Carbohydrates + Lean Protein)
When carbohydrates, whether fast or slow, are eaten with lean protein and very little fat, the body enters a glucose-focused phase.
Examples:
-
- Apple + non-fat Greek yogurt
- Potato + chicken breast
- Rice + trout
- Pasta + turkey breast
What happens:
-
- Blood sugar rises
- Insulin rises
- Glucose becomes the primary fuel
- Fat burning pauses briefly
This is normal.
Why does this support fat loss?
Because dietary fat is low:
-
- Insulin comes down faster
- Glucose clears efficiently
- Fat burning resumes sooner ⁶ ⁸
This allows carbohydrates, fast or slow, to be included without blocking fat loss.
[Click to learn more about the 6-Day Detox Drop]
How the Diet Free Life Methodology Looks at Carbohydrates
Within the Diet Free Life methodology, carbohydrates are classified as fast or slow carbohydrates.
Examples of fast carbs include:
-
- Potato
- Rice
- Apple
- Bread
Examples of slow carbs include:
-
- Broccoli
- Brussels sprouts
- Zucchini
- Carrots
Both fast carbs and slow carbs can be paired with lean protein when maximizing fat loss is the goal.
However, when a meal includes a fatty protein, such as steak, chicken thighs, or salmon, it is recommended to pair that protein with slow carbohydrates rather than fast carbohydrates to better support fat burning.
This helps:
-
- Keep insulin lower
- Avoid overlapping fuel signals
- Allow fat burning to continue
The most important takeaway is this:
The carbohydrate category matters far less than the pairing.
Where Fat Loss Can Break Down: Fast Carbs + Fat
Fat loss can be compromised when fast carbohydrates are paired with a high-fat diet, especially when the goal is to maximize fat loss.
Examples:
-
- Pizza
- Bagel + cream cheese
- Chips
- Apple + peanut butter
These combinations can:
-
- Raise insulin
- Keep insulin elevated longer
- Suppress fat burning
- Favor fat storage
Within the Diet Free Life methodology, regularly consuming high-fat, high-carbohydrate foods creates a metabolic barrier to fat loss.
This is not because the food is “bad,” but because fuel signals overlap, keeping fat burning turned off. ¹²
Protein and Fat Are Different
Protein paired with fat behaves very differently from fast carbohydrates paired with fat.
Examples:
-
- Eggs
- Salmon
- Steak + vegetables
- Chicken thighs + salad
Why this works:
-
- Insulin remains lower
- Fat remains the primary fuel
- Blood sugar stays stable
- Fat burning continues ⁶ ⁷
Food Quality Still Matters
Even within the same carbohydrate category, food quality matters.
For example:
-
- A baked potato and potato chips are both fast carbs
- The processed version triggers a stronger insulin response
Highly processed foods tend to:
-
- Raise insulin higher
- Keep insulin elevated longer
- Delay fat burning ⁸ ⁹ ¹³
The Real Problem: Constant Fuel Mixing
The issue is not carbohydrates.
The issue is not fat.
The real problem is mixing carbohydrates and fat together too often and for too long.
When this happens:
-
- Insulin remains elevated
- Fat burning rarely turns on
- Fuel switching breaks down
- Insulin resistance develops
- Fat loss stalls³ ⁶ ¹¹
This is a hormone-signaling issue, not a willpower issue.
The Simple Fat-Loss Strategy
To maximize fat loss:
When eating carbohydrates:
-
- Pair carbs (fast or slow) with lean protein
- Keep added fat low
When eating fat:
-
- Eat fat with protein
- If including carbs, favor slow carbs
Limit:
-
- Meals made mostly of fast carbohydrates + fat, especially daily
Final Takeaway
Fat loss is not about avoiding food or counting calories.
It is about using fuel the way the body was designed to use it.
When insulin signaling is respected:
-
- The Randle Cycle functions properly
- Fat burning turns back on
- Hunger improves
- Weight loss becomes easier
This is not a diet.
It is human physiology.
If you’d like to learn more about the Diet Free Life methodology and the 6-Day Detox Drop, where you can learn more about fast and slow carbs and how to properly combine foods to maximize fat loss, contact the person who shared this article, email me at robert@dietfreelife.com, or schedule a free consultation.
References
-
- Randle, P. J., Garland, P. B., Hales, C. N., & Newsholme, E. A. (1963). The glucose–fatty acid cycle: Its role in insulin sensitivity and the metabolic disturbances of diabetes mellitus. The Lancet, 281(7285), 785–789.
- Hue, L., & Taegtmeyer, H. (2009). The Randle cycle revisited. American Journal of Physiology-Endocrinology and Metabolism, 297(3), E578–E591.
- Czech, M. P. (2020). Insulin action and resistance in obesity and type 2 diabetes. Nature Medicine, 26(4), 485–497.
- Rosen, E. D., & Spiegelman, B. M. (2014). What we talk about when we talk about fat. Cell, 156(1–2), 20–44.
- Frayn, K. N. (2010). Adipose tissue as a buffer for daily lipid flux. Diabetologia, 53(10), 2037–2040.
- Wolfe, R. R. (2006). The underappreciated role of insulin in fat metabolism. The American Journal of Clinical Nutrition, 84(3), 475–482.
- Bikman, B. T. (2020). Why We Get Sick: The Hidden Epidemic at the Root of Most Chronic Disease—and How to Fight It. BenBella Books.
- Ludwig, D. S. (2002). The glycemic index: Physiological mechanisms relating to obesity, diabetes, and cardiovascular disease. JAMA, 287(18), 2414–2423.
- Hall, K. D., et al. (2019). Ultra-processed diets cause excess calorie intake and weight gain. Cell Metabolism, 30(1), 67–77.
- Kelley, D. E., & Mandarino, L. J. (2000). Fuel selection in human skeletal muscle in insulin resistance. Diabetes, 49(5), 677–683.
- Goodpaster, B. H., & Sparks, L. M. (2017). Metabolic flexibility in health and disease. Cell Metabolism, 25(5), 1027–1036.
- Fardet, A. (2016). Minimally processed foods are more satiating and less hyperglycemic. The American Journal of Clinical Nutrition, 104(3), 840–841.
- Monteiro, C. A., et al. (2019). Ultra-processed foods: What they are and how to identify them. Public Health Nutrition, 22(5), 936–941.
________
Robert Ferguson is a California- and Florida-based single father of two daughters, clinical nutritionist, Omega Balancing Coach™, researcher, best-selling author, speaker, podcast and television host, health advisor, NAACP Image Award Nominee, creator of the Diet Free Life methodology, and Chief Nutrition Officer for iCoura Health. He also serves on the Presidential Task Force on Obesity for the National Medical Association and the Health and Product Advisory Board for Zinzino, Inc.
🗓️ Schedule a FREE consultation with Robert Ferguson about becoming a client: SCHEDULE FREE CONSULTATION
👉🏽 To order the BalanceOil+ with the BalanceTEST, > CLICK HERE
👉🏽 Watch a free online presentation on the BalanceOil+ and the BalanceTEST: WATCH NOW.
Wow! This article is a MUST READ. Only Robert Ferguson could explain it with such clarity. It’s not just about losing weight; it’s about doing it the right way to be more effective and healthier in the long run. Take the time to read this article carefully. It is so worth it.