Complete Guide to Losing Fat
How can I lose fat? What's the difference between fat loss and weight loss?
First, it's important to understand the difference between weight loss and fat loss.
Body weight measures total mass (fat, water, bones, muscles, and organs).
Body fat isolates the amount of adipose tissue (fatty tissue) and visceral fat (around vital organs).
It's important to understand this distinction because body fat is the most accurate indicator and predictor of well-being and disease, while body weight and health are not always negatively correlated, meaning you can weigh more than average and still be healthier than average.

Now that we have that out of the way, let's move on to how body fat loss actually works.
How does fat loss work?
Body fat is gained when you maintain a positive energy balance over an extended period. This essentially means that your energy intake is greater than your energy expenditure: you're eating too much and not moving enough.
Research shows that people with a healthy weight should be able to maintain a zero energy balance, meaning energy in equals energy expended. [1]

As shown in the image above, a study published by the American Journal of Clinical Nutrition evaluated the change in calorie intake and average body weight from the decades 1970 to 2000. When comparing the change in average weight, the calculations almost exactly matched the increase in calorie intake. [2]
The point is, calories matter . Too many of them, and you'll find yourself gaining weight.
How many calories do I need per day?
You can calculate how many calories you need to eat by calculating your total daily energy expenditure (TDEE).
First, you need to calculate your basal metabolic rate (BMR), which is the number of calories you burn at rest. This will depend on your gender, weight, height, and body fat percentage. This constitutes the largest component of your TDEE (approximately 70%).
Second, you need to calculate the other 30%. This consists of:
- Non-exercise activity thermogenesis (NEAT). These are your random movements, like walking to the kitchen to get coffee, using hand gestures, etc.
- the thermic effect of food (TEF), which is the amount of calories burned to metabolize food;
- exercise activity thermogenesis (EAT) which explains the incremental temperature changes and effort expended during exercise.
To calculate your TDEE you can use this calculator:
to see how you are.
Does it matter what I eat? As long as you eat the right amount of calories?
Your TDEE tells you how many calories you burn per day, based on the statistics above.
If you eat more than this, you'll gain weight. If you eat less than this, you'll lose weight.
Correct?
Not necessarily.
For example, research shows that if you choose to eat 2,000 calories of junk food, you will metabolize this completely differently than 2,000 calories of nutrient-dense foods like whole grains or our very own Plenny Shake.
Simply put, you should consume a balance of protein, fat, carbohydrates, and the 26 essential vitamins and minerals. Don't avoid fat. It's an essential nutrient. Fat doesn't make you fat, but excess calories do.
In fact, a study published by The American Journal of Clinical Nutrition found that in a clinical trial of overfeeding, participants were better able to regulate energy balance when they were active and consuming healthy foods. This is due to an increase in NEAT, EAT, and TEF. [5]
So, when it comes to what you should eat and what you should avoid, choose nutrient-dense foods and avoid foods high in sugar and alcohol.

If you're struggling to eliminate certain things from your diet, these practical tips might help:
- If you regularly drink pure fruit juice, start diluting it with water but keep the same total ml per serving. Instead of 500 ml of juice, mix 300 ml of juice with 200 ml of water. That's a fantastic start!
- If you like crunchy snacks, like chips, try swapping them for popcorn and making your own.
- Have a sweet tooth? We understand. Who can say no to a good Belgian truffle? The trick to long-term weight loss is having control over what you eat. Instead of opting for the whole package, and so you don't deprive yourself of them, allow yourself to indulge in one or two. Truly enjoy it guilt-free and then move on with your day.
It will get easier every day!
If you continually decrease your calorie intake over time, studies show that your metabolism will slow down and also require less food intake due to the weight already lost. [6]
For example, if you were losing 1,500 pounds and then lose 5 pounds, your weight loss macros (based on your BMR) might now only be 1,300. In addition to this, after several months of restricting calorie intake, the hormonal mechanisms that stimulate appetite increase, making it harder to stick to your calorie goal. One example is a decrease in the hormone leptin, which makes you feel hungrier and less satiated. [7]

You can read more about this topic in our article on the science of hunger.
How do I count calories?
Tracking your calorie intake is easier than you think. It just takes a little preparation and determination.
It's great to make meal planning a habit. You can think about what you want to eat and buy the right products that contain the right amount of calories your body needs. When you first start doing this, it can be difficult to make it work. But after a few weeks, you'll notice how you get better at estimating the number of calories in the products you consume.
To make it easier to track your calorie intake, try using an app on your smartphone . One free app is called MyFitnessPal. It details every macro and micronutrient that enters your body. It calculates percentages for you so you don't have to waste time on complex calculations.
How to lose weight according to science? 10 steps:
Here's a handy checklist to help you:
- First, calculate your total daily energy expenditure: the number of calories you burn each day.
- Cut some calories out of your diet. For example, try consuming 500 fewer calories than you use per day for a week, and you could lose almost a pound.
- Make sure you give your body all the essential nutrients it needs.
- Start your weight loss journey by setting clear goals and incorporating them into your daily routine. Try changing your lifestyle and find what works for you.
- Stay healthy during the process. Get enough sleep, calm your mind, and drink plenty of healthy fluids.
- This takes time. Make sure you plan to achieve your goals realistically.
- Start tracking what you eat to make sure you don't exceed this calorie goal.
- Avoid empty calories. For example, avoid that extra tablespoon of olive oil and skip sugary sodas.
- Give your body time to adjust and stick with it. It'll feel normal soon enough.
- Focus on the right balance of nutrients and start increasing your activity, continuing to adjust your calorie goals as you begin to lose weight.
Dear friend, keep in mind...
If you're currently embarking on a weight loss journey, congratulations! You need patience and endurance, especially if you have a long way to go! So, well done for taking those first steps (or even leaps). There's just one thing you need to remember:
Weight loss is not linear.
You can stabilize, on the one hand, as already mentioned, due to metabolic adaptations while losing weight. On the other hand, you have fluid retention. We're mentioning this now so you don't get too frustrated in the future if this happens!
Your body can retain fluids for several reasons, two of the most common are:
- Hormonal (well, actually, menstrual) changes for women. You probably know what we're talking about: 1 to 2 kg more on the scale.
- The other is related to exercise. If you're training very hard, such as lifting weights or following certain high-intensity exercise protocols, your muscle mass will retain water due to regeneration.
Both situations happen. So don't step on the scale right after these events or look at it lightly. You'll get where you want to be; just be patient and kind to your body and stay well hydrated!
Drinking enough water will actually help reduce unwanted water weight, as this negatively regulates the ADH hormone. ADH monitors water balance, and too much of it actually causes water retention!
That's it! Oh, just one more tip.
Extra tip: measuring spoons
Measuring spoons make your portions as precise as possible. You'll really know if you're putting exactly one tablespoon of olive oil in your food or a quarter cup of cheese in your pasta.
If you want to make it even easier, you can try one of the following products. Each softened scoop of Plenny Shake contains the exact nutrients your body needs in the exact amount.
We hope this helps with your calorie control!
Sources
- Kevin D. Hall, Steven B. Heymsfield, Joseph W. Kemnitz, Samuel Klein, Dale A. Schoeller, John R. Speakman. Energy balance and its components: implications for body weight regulation, The American Journal of Clinical Nutrition, Volume 95, Issue 4, April 2012, Pages 989–994
- Boyd A Swinburn, Gary Sacks, Sing Kai Lo, Klaas R Westerterp, Elaine C Rush, Michael Rosenbaum, Amy Luke, Dale A Schoeller, James P DeLany, Nancy F Butte, Eric Ravussin. Estimating the changes in energy flux that characterize the rise in obesity prevalence, The American Journal of Clinical Nutrition, Volume 89, Issue 6, June 2009, Pages 1723–1728
- Ogden CL, Fryar CD, Carroll MD, Flegal KM. Mean body weight, height, and body mass index, United States 1960-2002. National Center for Health Statistics. Volume 27. October 2004. Pages 1-17.
- Scott Howell and Richard Kones. “Calories in, calories out” and macronutrient intake: the hope, hype, and science of calories. American Journal of Physiology-Endocrinology and Metabolism. November 2017 313:5, E608-E612.
- Hall, K.D., Heymsfield, S.B., Kemnitz, J.W., Klein, S., Schoeller, D.A., & Speakman, JR (2012). Energy balance and its components: implications for body weight regulation. The American journal of clinical nutrition, 95(4), 989–994.
- Benton, D., & Young, H.A. (2017). Reducing Calorie Intake May Not Help You Lose Body Weight. Perspectives on Psychological Science, 12(5), 703–714.
- Jeffrey M. Friedman, Leptin and the Regulation of Body Weight, The Keio Journal of Medicine, 2011, Volume 60, Issue 1, Pages 1-9, Released April 05, 2011, Online ISSN 1880-1293, Print ISSN 0022-9717