#157 - AMA #22: Losing fat and gaining fat: the lessons of fat flux
Peter Attia and Bob Kaplan delve into fat flux, explaining how fat enters and exits cells and determines body fat. They clarify that ketosis doesn't guarantee fat loss and distinguish between cosmetic fat removal and metabolically beneficial fat cell shrinkage, emphasizing the importance of understanding fat cell dynamics.
Deep Dive Analysis
6 Topic Outline
Introduction to AMA #22 and Fat Flux
Clarifying Fat Loss and Ketosis Misconceptions
Two Main Approaches to Reducing Fat Mass
Metabolic Effects of Liposuction vs. Dietary Fat Loss
Understanding Fat Flux at the Cellular Level
Technical Overview of White Adipose Tissue (WAT)
3 Key Concepts
Fat Flux
Fat flux refers to the net movement of fatty acid substrate into and out of a fat cell. This balance determines whether a fat cell accumulates fat and gets larger, or releases fat and gets smaller, ultimately impacting a person's total fat mass.
Shrinking Fat Cells vs. Reducing Fat Cell Number
Shrinking existing fat cells, typically through dietary interventions, leads to significant metabolic improvements. In contrast, reducing the total number of fat cells, such as through liposuction, is primarily a cosmetic procedure with different and less profound metabolic benefits.
White Adipose Tissue (WAT)
WAT is the most common type of fat tissue, which stores fat and functions as an endocrine organ. It is distinct from brown adipose tissue (BAT), which has unique metabolic properties and a higher concentration of mitochondria.
5 Questions Answered
Not necessarily. You can be a 'fat burning machine' or in ketosis and still accumulate fat if the net flux of fat into your fat cells is greater than the efflux.
When people say they want to lose weight, they typically mean they want to lose fat mass, which translates to wanting their fat cells to be smaller.
One approach is to reduce the total number of fat cells (e.g., via liposuction), and the other is to shrink the existing fat cells (e.g., via dietary intervention).
Yes, there is a profound difference. Reducing the number of fat cells (liposuction) is primarily a cosmetic procedure, while shrinking fat cells (dietary intervention) leads to significant metabolic improvements.
By understanding the 'fat flux,' which is the net balance of fatty acid substrate entering and exiting the fat cell. If more goes in than out, it gets larger; if more goes out than in, it gets smaller.
7 Actionable Insights
1. Shrink Fat Cells for Health
Prioritize reducing the size of your fat cells through interventions like diet, as this approach provides significant metabolic improvements beyond just cosmetic benefits. Reducing the number of fat cells (e.g., via liposuction) is primarily a cosmetic procedure and does not offer the same metabolic advantages.
2. Ketosis Not Fat Loss Guarantee
Do not assume that being in ketosis or becoming a ‘fat burning machine’ automatically leads to fat loss or prevents fat accumulation. It is possible to gain weight and fat even while in ketosis, so relying solely on this state for fat loss is a misconception.
3. Redefine Weight Loss as Fat Loss
When aiming to ’lose weight,’ understand that the true goal is to lose fat mass, which fundamentally means making your fat cells smaller. This reframing helps clarify the objective and guides more effective strategies.
4. Clarify Fat Loss & Muscle Gain
Define your body composition goals clearly: typically, people aim to lose fat and gain muscle, rather than just losing or gaining ‘weight.’ This precise goal setting helps in choosing appropriate strategies.
5. Understand Fat Flux Dynamics
To comprehend how fat cells change size, apply an ’engineering problem’ mental model by tracking the net ‘flux’ of fatty acid substrate – what goes into the cell versus what comes out. A net accumulation makes the cell larger, and a net release makes it smaller.
6. Adipose Tissue Flux vs. Calories
While ‘calories in, calories out’ describes overall energy balance, understand that fat loss or gain specifically occurs at the level of the adipose tissue, involving how much fat enters, is released from, and is trapped within fat cells. This provides a more granular understanding than just systemic energy balance.
7. View Diagrams for Clarity
If listening to the audio version of the podcast, pause and refer to the show notes for diagrams or watch the video version to better understand complex visual explanations, such as the white adipose tissue diagram.
3 Key Quotes
You can absolutely be in ketosis and gain weight. You can absolutely be quote unquote fat burning machine and still accumulate fat.
Peter Attia
We should never confuse the metabolic benefits that come from reducing the size of adipose tissue with reducing the amount of it.
Peter Attia
If we didn't understand fat flux, there would be no flux capacitor.
Peter Attia