Eat less. Exercise more. Sleep early. Drink more water.
I’m sure you’re wondering, “Wait, is that it? My mum could have told me that.”
And you are absolutely right.
Everywhere you go, weight loss is advertised. It’s a magical buzzword that “fitness personalities” or “diet doctors” use when they want to sell their products; from workout routines to crash diets. They market weight loss as if it were easy, but it never seems to work. How will you lose weight now?
Fret not, for today we will discuss weight loss; how it works and how we can make it work for ourselves. There will be no scientific mumbo jumbo, just basic concepts and principles.
How weight loss works
Before we understand how we can lose weight, we need to first understand how your body consumes energy for its daily needs. How we measure energy used in the body (or contained in food) is through calories (cal) or kilojoules (kJ). That said, we’ll use calories in this article.
Now, your body uses energy for its life processes (like breathing, walking, staying awake or blinking your eyes), and we replenish that energy that we spend by eating. The average woman aged 20-40 requires 1800-2400 calories a day, while a man of similar age would require 2000-3000 calories a day. (The Office of Disease Prevention and Health Promotion (ODPHP) (US), 2015-2020)
Of course, your daily requirements would differ from the next person, based on factors including but not limited to your genetic makeup, age and level of activity (Gray, 2013). Nonetheless, the energy requirements mentioned above are good as general guidelines when considering how much energy you spend and require in a day.
Now how does the body process energy? Let us begin by assuming you eat 3000 calories a day and your body requires 3000 calories a day.
The body ingests and digests the food that you eat, and it just so happens that it uses up all the energy that comes from it. There is 0 net energy (or calories) remaining from what you’ve just eaten over the day. There is no excess or deficit of calories in your body. The consumption of energy = the expenditure of energy.
But let’s say you consume 4000 calories worth of food a day. Now using the math before (consumption of energy – expenditure of energy), you’ve now an excess of 1000 calories sitting in your body. Your body now takes this energy and stores it away in your body for a rainy day, as fat in adipose cells in your body, and these fat cells contribute to extra weight on your body. This is the how weight is gained, where the input of energy exceeds the output of energy.
Let’s reverse the scenario and say that you eat 2000 calories worth of food a day. Where’s the 1000 calories going to come from? Your body needs that energy to continue functioning, so it begins to take the energy from the stores in your body (fat from the adipose cells or protein from your muscles). That mass that’s lost through your body’s energy consumption will result in a loss in weight. (Whitney, 2018)
Calorie deficit and basal metabolic rate (BMR)
So, we’ve come to a conclusion. Weight loss is achieved through a calorie deficit.
Now, it’s important to understand from the get-go that most of the energy spent during the day (or night) is when you’re going about the things you do all the time. Like sitting down and reading a book or doing your work at your desk. This is what we call the basal metabolic rate (BMR), and it varies from person to person. A growing child (or a teenager) would naturally have a higher BMR, as rapid bone and muscle growth increases their need and consumption of energy, which explains why puberty’s when most children lose their “baby fat”. Meanwhile, people who lead sedentary lifestyles and the elderly tend to have lower BMRs, as their bodies require less energy. If you want to have an estimate on your BMR, you can visit your local doctor or health professional.
For the average adult in modern times, a sedentary lifestyle has become the norm. We spend 8-10 hours a day at our desks, exercising maybe once a week. How then do we put ourselves in a calorie deficit? In this article we will focus on improving your diet to achieve your caloric deficit.
Improving your diet
There are ways to achieve your caloric requirements every day, some of which are good and most of which are bad. In this modern age, most of our foods are highly processed to contain high amounts of:
1. Sugar – Like high fructose corn syrup, normally found in high sugar sweets and snacks like Mars bars, Kitkats and many of our soft drinks.
2. Salt – Most processed foods contain high amounts of sodium chloride (or table salt) as a preservative or to improve taste.
3. Fat – Fat normally refers to saturated fats found in food, especially foods from animal sources, cured meats, or fatty meat. Plants, however, contain unsaturated fat, which differs from saturated fat somewhat.
On their own and in controlled amounts, we do need the above mentioned as nutrients in the body; sugars are our carbohydrates, which are our main sources of energy. Sodium is required as an electrolyte in the body and fats (saturated and unsaturated) are necessary as essential components for neural development and joint health. In addition to these, we must eat sufficient fibre (usually from plant sources) and protein (meat, legumes or nuts) and drink enough water to have a healthy diet.
However, most of the food that we consume daily are in excess. The main source of energy in the body, as mentioned before, would be carbohydrates (aka sugars), but fat and protein also contribute to your caloric count. Excess fat and protein would also contribute to weight gain if the calories are not used up by the body.
Our diet should thus be proportioned to the following: 25% carbohydrate, 25% protein and 50% for fruits and vegetables, which is graphically represented below!
The healthy plate explained:
Here is a short explanation on why the healthy plate works and why vegetables would seem to take up most of the plate.
An average adult (assuming you need 2000-3000cal a day) would require the following amounts of food a daily:
1. 250-350g of carbohydrates – 1g of carbohydrate contains 4cal
2. 20-30g of protein – 1g of protein contains 4cal
3. 20-30g of fat – 1g of fat contains 9cal
4. 25-40g of fibre
This seems logical, we tend to eat a lot more carbohydrates than anything else, so why are vegetables so prominent on the plate? Let us compare the 2, using white rice and broccoli as comparisons (fatsecret.com, 2020):
Comparing the two, we can tell that at the same weight, broccoli would have a significantly lower amount of carbohydrates while containing much more dietary fibre, making it exceptional for consumption in larger quantities during your meals. Vegetables also contain larger quantities and numbers of other micronutrients (like Iron and Zinc) and vitamins. By eating more vegetables during your meals, you fill your stomach up faster and quicker with fewer calories and with healthier nutrients and vitamins. Win-win!
You can also use this concept for comparing the way how food is cooked. See below for a comparison between roasted and fried chicken. By comparing their nutritional information, we can conclude that roasted chicken would almost always be the healthier choice, with less fat, sodium and calories while maintaining a good amount of protein.
While this has just been a general overview of how nutrition can directly affect your journey in weight loss, you can also refer to future articles from this fitness space for more information on healthy food choices! (Poehlman, 1995)
Why some diets and routines do not work
There are diets and routines that are marketed to us all the time, with catchy names like the “Keto diet” or the “Caveman (paleo) diet”. Similarly, with workouts, with influencers posing with lean abs and arms, promising abs in “2 weeks” or visible progress in a month. The routines and diets are structured in ways that require you to tailor your habits and practices to fit them for them to work. It is vital to understand the requirements and limitations before you decide to take up a certain diet or routine, as those would ultimately affect one of the most important factors in weight loss, sustainability.
These diets are sometimes known as “crash diets”, where they want to achieve weight loss (not always fat mass) in a certain time period (usually days). They achieve this by requiring you to restrict the amount and/ or the type of food that you can consume.
After achieving the desired weight loss, people normally revert to their usual eating patterns, quickly regaining any lost weight. That is why crash diets don’t work. Some that you might have heard of would be juice cleanses, “souping” or the caveman (Paleo) diet.
Weight loss (and especially fat loss) that is sustainable and long-lasting requires commitment and lifestyle changes. It is better to make healthy changes to your diet and stick to them for a period of 6 to 12 months.
Many of the diets that are blasted on advertisements don’t call for sustainability, they promise results in a few weeks or days. Try and apply the principles that we elaborated on in this article, while seeking guidance from health professionals (who you can find on our website right here!), in order to build a routine and diet that is best suited to you. (UEDA, 2016)
Weight loss is not impossible, it’s just misunderstood. Stay tuned for our next article where we elaborate more on how exercise and activity affect how we can control our weight too.
- Nathaniel Liew (NUS)
- Jackie Sim (NUS)
- Wymann Tang (NUS)
- Rachel Goon (NUS)
- Hazel Soh (NUS)
- Clare Cheong (NUS)