Weight loss is a long journey, and nutrition is the key to getting you to your destination safely and sustainably. Many people often start by trying a series of popular diets: from low-carb, keto, intermittent fasting to detox. But the truth is that there is no one-size-fits-all formula. What will help you maintain it long-term is a scientific, flexible and easy-to-apply diet in your daily life.
What is the best diet for sustainable weight loss?
Here are 5 core principles to build an optimal diet for weight loss. These are not short-term tips, but a solid foundation for you to maintain a healthy weight over the long term.
1. Focus on whole, minimally processed foods (90% of the time)
Imagine your body as a sophisticated machine. To run smoothly, it needs “clean” fuel. Whole, minimally processed foods are that fuel.
Foods like vegetables, fresh fruits, whole grains, unsalted nuts, lean meats, fresh fish, eggs… provide not only calories but also fiber, vitamins, minerals and health-beneficial compounds. They help you stay full longer, keep blood sugar stable and reduce the risk of “mindless snacking”.
In contrast, processed foods (like snacks, cakes, fast-fried foods) are often high in sugar, salt, bad fats but low in nutrients. Eating a lot of these foods is like taking in “dirty fuel” that can create instant energy but leave long-term consequences.
Some studies show that people who maintain a diet rich in whole foods not only lose weight more effectively, but also improve cardiovascular health, digestion and overall energy.
Apply the 90/10 rule. That means 90% of your diet comes from whole foods, the remaining 10% is for self-indulgence.
For example, you can have pizza on the weekend or a small piece of cake at a birthday party, without feeling guilty. This helps you avoid the feeling of scarcity, which is the reason why many people give up when dieting too strictly.
2. Supplement adequate protein in every meal
If carbohydrates are a source of quick energy, then protein is like the “bricks” to build and maintain the body. When you lose weight, protein plays an extremely important role because it:
- Creates a feeling of fullness for a long time, limiting cravings.
- Supports muscle maintenance, even when you are losing fat.
- Increases the “thermic effect” of food: the body burns more calories to digest protein than fat or carbs.
A reasonable amount of protein in each meal is about 1.5–2 palms (equivalent to 30–40g). Protein sources can come from lean meat, fish, chicken, eggs, or if you are vegetarian, you can replace them with tofu, lentils, tempeh.
Suggestions:
- Breakfast: 2 fried eggs + 1 slice of whole wheat bread + some steamed vegetables.
- Lunch: Grilled chicken breast with colorful salad.
- Dinner: Pan-fried salmon, served with boiled vegetables and brown rice.
Prepare protein in the fridge (for example, pre-boiled eggs, grilled chicken breast or steamed fish and then divide it into small pieces), when you are busy, you just need to reheat and combine it with vegetables.
If you often crave snacks, instead of snacks, try unsweetened Greek yogurt or some almonds, which are both rich in protein and lower in calories.
Nutritionists say that a high-protein diet helps you lose weight more sustainably than a low-protein diet, because it helps the body maintain lean mass (muscle) instead of losing both muscle and fat.
3. Eat 3–4 main meals a day and limit snacking
A common mistake when losing weight is to snack constantly with the excuse of “eating less but dividing into many meals”. In fact, if you do not control well, snacking can easily lead to excess calories without you realizing it.
Instead of snacking, focus on 3 main meals, or 4 meals if you get hungry easily. It is important that each meal has enough protein, green vegetables and a healthy amount of carbs.
This helps:
- Keep blood sugar stable.
- Limit cravings for sweets.
- Help you be more proactive in planning your meals.
For example: People with low appetite: 3 main meals (breakfast, lunch, dinner). If you are someone who often craves snacks, add a snack in the afternoon, but it is a small meal, not a snack (For example: 1 box of Greek yogurt with fresh fruit).
Tip: Set a fixed meal schedule. Once your body gets used to it, you will rarely feel cravings due to emotions or fluctuating hormones (false hunger). At the same time, you should avoid eating while watching TV or your phone, because it is easy to eat more without realizing it. Some observational studies show that people who eat at fixed meals tend to maintain a more stable weight than those who eat irregularly and snack a lot.
4. Eat vegetables at every meal (except breakfast)
Vegetables are almost indispensable “companions” if you want to lose weight. They are rich in fiber, vitamins, minerals, and low in calories. Eating more vegetables helps you feel fuller without consuming too much energy.
For example:
- Lunch: Vegetable salad mixed with olive oil, served with salmon.
- Dinner: Steamed vegetables (broccoli, carrots, zucchini) with lean meat.
You may not necessarily have to eat vegetables at breakfast, but you should definitely have them at lunch and dinner.
Practical tip: Eat vegetables before the main meal. Many people find that when they do, they eat less rice or high-calorie foods. Try to vary the way you prepare them, such as steaming, boiling, grilling, mixing in salads, or lightly stir-frying. When meals are colorful and flavorful, you are less likely to get bored.
Research shows that people who eat at least five servings of fruits and vegetables a day tend to be healthier and have a lower risk of chronic disease.
5. Intermittent fasting for 12–14 hours overnight
You don’t need to follow a strict form of fasting. Just letting your body “rest” for 12–14 hours overnight is enough to create many benefits.
For example, if you eat dinner at 7 p.m., stop eating after that and only eat breakfast again at 7–9 a.m. the next morning. This time period helps:
- The body regulates hormones, including insulin and growth hormone.
- Reduces the risk of evening snacking.
- Supports deep sleep and a more flexible metabolism.
Practical tip: If you have a late-night craving, drink a glass of warm water or light herbal tea. Often, the feeling of “hunger” is just the body being thirsty. Set a reminder: for example, 8pm is the time to stop eating.
Some studies on intermittent fasting show that eating at a reasonable time frame can help the body burn fat more effectively, while reducing the risk of metabolic disorders.
In short, losing weight is a journey of learning how to make smart food choices and creating sustainable habits. And the 5 principles above are the foundation to help you go the long way without feeling forced. When you eat moderately, balanced and comfortably, losing weight will no longer be a burden, but become a natural part of a healthy lifestyle.
