ALFA NUTRICIÓN Y FITNESS
Otay Universidad, Tijuana, Baja California
Specialized care for patients in Tijuana, San Diego, and surrounding areas
Losing Fat Should Not Mean Losing Muscle
When a person decides to lose weight, they generally focus on a specific number on the scale. However, from a clinical nutrition and body composition perspective, body weight alone does not tell the whole story.
A reduction in body weight can include the loss of body fat, but also water and muscle tissue. Therefore, a well-designed nutritional strategy should not have the sole objective of “weighing less,” but rather reducing body fat while protecting muscle mass.
This concept is especially important in Mexico, where excess weight represents a significant public health problem. According to ENSANUT Continua 2023, 37.3% of Mexican adults were overweight and 38.9% had obesity; in other words, approximately three out of every four adults had overweight or obesity.
In addition, obesity was associated with higher odds of type 2 diabetes, hypertension, and dyslipidemia in ENSANUT analyses.
For this reason, losing fat should be understood as a health intervention and not merely as an aesthetic goal.
The right question is not:
“How much weight can I lose?”
Instead:
“How much fat can I reduce while maintaining as much muscle, strength, and functionality as possible?”
What Does It Mean to Lose Fat Without Losing Muscle?
Losing fat without losing muscle means reducing body fat through a controlled energy deficit while using strategies designed to preserve lean body mass.
Muscle mass is a fundamental component of body composition. It contributes to movement, strength, physical function, and different metabolic processes.
On the other hand, subcutaneous fat is the fat located beneath the skin, while visceral fat accumulates around internal organs and has greater metabolic relevance.
Therefore, two people can weigh exactly the same and have completely different body compositions.
One person may have:
- A higher percentage of muscle mass.
- Less body fat.
- Less visceral fat.
- Greater strength and functionality.
While another person may have:
- Less muscle mass.
- A higher body-fat percentage.
- Greater visceral fat accumulation.
- Lower physical capacity.
This demonstrates why a professional strategy should analyze body composition, not just body weight.
Why Is Muscle Lost During a Diet?
When there is an energy restriction, the body needs to use its reserves to meet its energy requirements.
If the strategy is too aggressive, the risk of losing lean body mass may increase.
A meta-analysis on resistance training and energy deficits found that energy deficits can impair lean-mass gains, particularly when they are prolonged or excessive.
Some of the mistakes that can contribute to muscle loss include:
- Reducing calories too drastically.
- Consuming too little protein.
- Eliminating entire food groups unnecessarily.
- Not performing resistance training.
- Doing excessive cardiovascular exercise.
- Sleeping too little.
- Following extremely restrictive diets.
- Seeking results too quickly.
- Failing to adjust the plan as body weight changes.
Therefore, a good nutrition strategy should seek a balance between fat loss, energy availability, protein intake, training, and recovery.
The Role of Protein in Preserving Muscle Mass
Protein provides the amino acids necessary to maintain and repair muscle tissue.
During a period of fat loss, ensuring adequate protein intake can be particularly important.
A systematic review and meta-analysis published in 2024 found that higher protein intake helped prevent reductions in muscle mass in adults with overweight or obesity who were attempting to lose weight. The authors observed better muscle preservation with intakes above approximately 1.3 g/kg/day, although individual needs should be assessed.
This does not mean that everyone should consume exactly the same amount of protein.
Protein requirements depend on factors such as:
- Body weight.
- Body composition.
- Age.
- Physical activity level.
- Training.
- Goals.
- Health status.
- Energy availability.
Protein sources may include chicken, fish, lean meat, eggs, dairy products, legumes, soy, and other alternatives according to individual preferences and nutritional needs.
Resistance Training: A Fundamental Tool
If the goal is to lose fat while preserving muscle, resistance training should play an important role in the strategy.
Weight training, machines, resistance bands, or bodyweight exercises provide a stimulus that helps the body preserve and develop muscle tissue.
The evidence supports this strategy. A recent systematic review and meta-analysis found that incorporating resistance training during weight loss helps protect lean body mass, increases fat loss, and improves muscular strength.
Therefore, a person who wants to improve body composition should not rely exclusively on walking, running, or cardiovascular exercise.
The goal is to combine:
Proper nutrition + resistance training + physical activity + recovery.
The World Health Organization recommends that adults perform at least 150 minutes of moderate-intensity physical activity per week, along with muscle-strengthening activities involving the major muscle groups on two or more days per week.
How Quickly Should You Lose Fat?
One of the most common mistakes is believing that the faster you lose weight, the better the results will be.
In reality, losing weight too quickly can make it more difficult to preserve muscle mass and maintain the results.
There is no universal rate of weight loss that is appropriate for everyone.
The strategy should consider:
1. Starting Point
A person with a higher amount of body fat may respond differently from someone who already has a relatively low body-fat percentage.
2. Body Composition
Losing weight while having a high amount of muscle mass is not the same as losing weight when muscle mass is already low.
3. Training
A person who regularly performs resistance training will have different nutritional needs from someone who is sedentary.
4. Health Status
Diabetes, hypertension, metabolic abnormalities, medications, and other health conditions may modify the appropriate approach.
Therefore, the goal should be to make sustainable progress, not simply to lose the greatest possible number of kilograms.
How Does a Personalized Nutrition Approach Work?
At ALFA Nutrición y Fitness, the goal is not to provide a generic diet that simply tells the patient to “eat less.”
The process begins with an evaluation.
1. Initial Assessment
Factors such as the following are reviewed:
- Personal and family medical history.
- Current eating habits.
- Physical activity.
- Training.
- Schedule.
- Food preferences.
- Sleep.
- Goals.
- Metabolic risk factors.
2. Body Composition Assessment
When indicated, body composition assessment tools may be used to complement the available information.
This allows changes in the following to be monitored:
- Body weight.
- Body-fat percentage.
- Muscle mass.
- Circumferences.
- Body-fat distribution.
In this way, progress does not depend exclusively on the scale.
3. Defining the Goal
The objective may be to:
- Reduce body fat.
- Maintain muscle mass.
- Improve the percentage of muscle mass.
- Improve athletic performance.
- Improve metabolic parameters.
- Improve healthy habits.
- Achieve body recomposition.
4. Designing the Nutritional Strategy
The plan may establish individualized targets for:
- Energy.
- Protein.
- Carbohydrates.
- Fats.
- Fiber.
- Hydration.
- Meal distribution.
It should also take the patient’s real life into consideration.
A plan that works from Monday through Friday but becomes impossible during weekends, travel, restaurant meals, or social gatherings is not truly a sustainable strategy.
The Importance of Measuring More Than Body Weight
One of the most important changes in modern nutrition is moving away from interpreting success exclusively through the scale.
A person may lose only a few kilograms and nevertheless experience significant changes in body composition.
For example:
Less fat + preserved muscle = better body composition.
In some cases, body recomposition can even occur, in which body fat decreases while muscle mass is maintained or increased.
Therefore, indicators such as the following can be useful:
- Waist circumference.
- Body-fat percentage.
- Muscle mass.
- Strength.
- Performance.
- Progress photographs.
- Energy levels.
- Clinical parameters.
Healthy Habits You Can Start Today
You do not need to change your entire diet overnight.
1. Include Enough Protein
Try to include a source of protein in your main meals.
2. Increase Vegetables and Fiber-Rich Foods
These can improve overall dietary quality and promote satiety.
🏋️ 3. Perform Resistance Training
Incorporate resistance training progressively and consistently.
4. Move Throughout the Day
Walking and reducing sedentary time also contribute to energy expenditure and overall health.
5. Maintain Adequate Hydration
Water should be the primary source of hydration for most people.
6. Prioritize Recovery and Sleep
Recovery is part of any strategy aimed at improving body composition.
7. Evaluate Your Progress Correctly
Do not allow a single number to determine whether you are making progress.
Look at trends and multiple indicators.
Nutritional Treatment Requires Synergy Between the Patient and the Professional
A professional nutritional strategy cannot work if only one side is committed.
The professional contributes:
- Assessment.
- Scientific knowledge.
- Data interpretation.
- Nutrition education.
- Planning.
- Follow-up.
- Adjustments.
The patient contributes:
- Consistency.
- Communication.
- Active participation.
- Honesty during follow-up.
- Willingness to modify habits.
If a strategy is not working, the solution is not necessarily to blame the patient or abandon treatment.
First, we should ask:
“What is preventing the plan from being sustainable?”
It could be hunger, scheduling, lack of organization, stress, insufficient recovery, difficulty eating outside the home, or simply an overly restrictive strategy.
Identifying the obstacle allows the treatment to be modified.
The Mexico and Tijuana–San Diego Context
Excess weight represents an important reality in Mexico. ENSANUT Continua 2023 reported that 76.2% of men and 76.3% of women aged 20 and older had overweight or obesity.
This demonstrates that the issue goes far beyond aesthetics.
An unfavorable body composition can be accompanied by a greater risk of metabolic abnormalities. In ENSANUT analyses, obesity was associated with higher odds of type 2 diabetes, hypertension, and dyslipidemia.
In a border region such as Tijuana–San Diego, many people also have long workdays, eat away from home, or commute daily between both sides of the border.
For this reason, a nutritional strategy must adapt to the patient’s reality.
Effective nutrition should not work only inside a consultation room.
It must work in everyday life.
Does Losing Fat Mean Eating Very Little?
No.
The goal of a professional strategy is not to place the patient under extreme restriction.
Evidence indicates that combining energy restriction with exercise and adequate protein intake may promote better body composition than relying on energy restriction alone.
The question should not be:
“How little can I eat?”
Instead:
“What is the minimum level of restriction necessary to achieve results while protecting my muscle mass, performance, and health?”
This change in perspective can make the process much more sustainable.
Conclusion: Lose Fat, but Do It Strategically
Losing fat without losing muscle requires much more than simply reducing calories.
An evidence-based strategy should integrate:
Appropriate energy deficit + sufficient protein + resistance training + physical activity + recovery + monitoring.
Muscle mass is an important component of health and physical function, while reducing excess subcutaneous fat and visceral fat can contribute to improving body composition and certain metabolic risk factors.
Therefore, success should not be measured solely by how many kilograms disappear from the scale.
The true objective is to achieve better body composition, preserve as much muscle mass as possible, and develop habits that can be maintained over the long term.
At ALFA Nutrición y Fitness, strategically located in Otay Universidad, Tijuana, Baja California, we work with patients from Tijuana, San Diego, and surrounding areas through individualized nutrition strategies focused on body composition, metabolic health, performance, and overall well-being.
If you have tried to lose weight and feel that you are losing muscle, energy, or performance in the process, it may be time to move beyond generic strategies and have your situation professionally evaluated.
ALFA Nutrición y Fitness — Otay Universidad, Tijuana, B.C.
618 367 1111
Schedule a strategic consultation and begin working on a nutritional strategy designed around your body, your goals, and your reality.
