IMAGO NUTRITION

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Top 5 Priorities for Fat Loss (According to Science)

Reviewed By Danielle Glesne, RDN, LD, CDCES

There is no shortage of claims about what people should do in order to lose weight/fat.

It can be difficult to know which are true, and of those that are true, which to prioritize.

So let’s take an evidence-based approach to understanding what your priorities should be when losing weight/fat, shall we?

1. Negative Energy Balance

Commonly referred to as a calorie deficit or an energy deficit, a negative energy balance—where you consume less calories than you expend on average over time—is the single determining factor in weight loss.

If you consume fewer calories than your body expends in a day, you put your body in a negative energy balance. If your body remains in a negative energy balance over time, the outcome is weight loss (PMID: 22434603).

This is why any discussion about body weight—whether going up, going down, or staying the same—must begin with energy balance.

For a closer look at energy balance, read my article: What is Energy Balance (And Why Does It Matter)?

2. Protein Intake

Optimal protein intake has been shown to play a critical role in weight/fat loss, by helping boost metabolism, reduce appetite and cravings, change several weight-regulating hormones, and prevent muscle loss.

Boosts Metabolism

Current evidence suggests a high-protein diet can increase the number of calories your body burns by boosting your metabolic rate and decreasing appetite. (PMID: 25489333)

Evidence has shown consuming 25–30% of your total daily calories from protein can increase calories burned by up to 80–100 calories per day, compared with lower protein diets. (PMID: 19640952; PMID: 11838888; PMID: 20565999)

Reduces Appetite and Cravings

Studies have also shown protein is more effective than fats or carbohydrates at keeping you feeling full, which can contribute to consuming fewer calories. (PMID: 8862477; PMID: 15466943)

One study in men with obesity showed consuming 25% of calories from protein increased their feeling of fullness, and reduced their late-night snacking desires by 50% and their obsessive thoughts about food by 60%. (PMID: 20847729)

Changes Weight-Regulating Hormones

Some of the most important signals the brain receives are hormones that change in response to feeding (PMID: 19946401).

Optimal protein intake increases levels of the satiety (aka appetite-reducing) hormones such as GLP-1, peptide YY, and cholecystokinin, while reducing levels of the hunger hormone ghrelin (PMID: 16400055; PMID: 22188045; PMID: 16469977).

By increasing protein as a percentage of overall calorie intake, you feel fuller and less hungry, which can lead to consuming less calories—helping maintain the negative energy balance we discussed above.

Prevents Muscle Loss

Optimal protein intake can also reduce muscle loss, which can help maintain a higher metabolic rate during the weight/fat loss process (PMID: 23446962; PMID: 19927027; PMID: 16046715).

For more on optimal protein intake relative to various goals, read my article: How Much Protein Should You Eat in a Day?

3. Strength Training

Among its many, many benefits, strength training is an often-overlooked priority in the weight/fat loss process. We often associate lifting weights with getting bigger, or gaining weight. And while—with great intentionality—that certainly can occur, strength training is terrific for weight/fat loss as it can increase metabolism, help your body burn calories more efficiently, and reduce body fat.

Increases Metabolism

First, building muscle increases your body’s basal metabolic rate (BMR)—which is the number of calories your body burns at rest (PMID: 25293431).

Helps Burn Calories Efficiently

Further, studies have shown that your metabolic rate can be increased up to 72 hours after strength training (PMID: 32397898; PMID: 23566074).

I often refer to this as the “compounding effect” of strength training, as your body continues to burn additional calories for up to 3 days from the initial workout.

Reduces Body Fat

While its true that muscle is to be gained due to strength training, research has also shown that fat can be lost as a result of strength training—particularly abdominal fat.

Abdominal fat stored around the abdomen (particularly visceral fat) is associated with an increased risk of chronic diseases such as heart disease, nonalcoholic fatty liver disease, type 2 diabetes, and certain types of cancer.

Multiple studies have shown the benefit of strength-training exercises for reducing abdominal and total body fat (PMID: 32804997; PMID: 25530447; PMID: 30774600).

4. Sleep

This one may surprise you, but sleep is an oft-overlooked priority for weight/fat loss, as it helps fight cravings, reduce calorie intake, keep your metabolic rate high, reduce muscle loss, and prevent insulin resistance.

Helps Fight Cravings

Research shows us that insufficient sleep can alters the way our brains work. There is evidence to suggest this makes it more difficult to make healthy choices and avoid tempting foods (PMID: 22357722).

Additionally, studies have found an insufficient amount of sleep can increase your affinity for foods that are high in calories (PMID: 15583226; PMID: 21715510).

Reduces Calorie Intake

Very practically, more time awake usually leads to more calories consumed.

One study found when participants were only allowed to sleep for 4 hours, they consumed 559 more calories on average the following day, compared to when they were allowed to sleep for 8 hours (PMID: 20357041).

Keeps Metabolic Rate High

Inadequate sleep may also cause your metabolic rate to slow, meaning your body burns fewer calories at rest (PMID: 26538305).

Reduces Muscle Loss

As we learned in the strength training, gaining and maintaining muscle aids in the weight/fat loss process.

One weight loss study found that while all participants were in a negative energy balance, those who slept 8.5 hours lost less weight from muscle that participants who slept 5.5 hours (PMID: 20921542).

Prevents Insulin Resistance

Research has also discovered that inadequate sleep can cause cells in the body to become insulin resistant (PMID: 24011890).

Insulin resistance is a state where increased sugar resides in the bloodstream which causes the body to produce more insulin to compensate—which is a precursor for type 2 diabetes as well as excess weight gain.

5. Cardio

While strength training helps your body burn more calories over time, cardio burns more calories at one time.

This can be an important factor in helping tilt the energy balance to ensure your body is expending more calories than its consuming (remember: a negative energy balance is required to lose weight/fat).

How Much Cardio for Weight Loss?

The U.S. Department of Health and Human Services recommends at least 150-300 minutes of moderate-intensity—or 75-150 minutes a week of vigorous-intensity—aerobic exercise each week to see substantial changes in body composition (Physical Activity Guidelines for Americans, 2nd Edition).

In order to lose 1lb of body weight in one week, we need to create a negative energy balance totaling 3,500 more calories burned than consumed, an average of 500 calories per day.

Depending on several factors (i.e. age, body composition, gender, intensity, duration, etc.), your body will burn a varying amount of calories during various forms of cardiovascular training.

Cardiovascular Health

That said, some form of cardiovascular training—whether that’s walking, running, cycling, swimming, hiking, etc.—is not only beneficial for weight/fat loss, but beneficial also for cardiovascular health.

And with heart disease being the single greatest cause of premature death in the United States and around the world, that can’t be understated.

Because none of this matters if you’re not here. :)

Questions?

Could you use guidance on what all this means for your individual context and goals, and a coach in your corner to help achieve those goals?

Don’t hesitate to CONTACT ME.

I’m here to help.