Human biology and modern life
Your body has not changed. The environment has. Once you understand why your body reaches for the familiar and the easy, it becomes easier to work with it than to fight it every day.
Old wiring, new environment
The human body developed slowly, across generations. A preference for energy-dense food and a tendency to save effort can be one way to understand how people adapt to their surroundings.
Modern daily life is different in many ways. Food is readily available, and some everyday situations require less movement than before. That can help explain why choices sometimes feel conflicted, without using one biological account as an explanation for everyone.
The environment influences choices, but each person's situation is its own whole.
Why this feels like a constant fight
When modern daily life meets familiar preferences, a conflict can appear: you know what you want to do, but familiar and easily available options pull in another direction.
Willpower is not the only way to look at this. Tiredness, rushing, habit and the environment can affect which choices feel easy in a given moment.
Looking calmly at your own situations can reveal ways to adjust routines or surroundings that fit your life.
When biology meets modern life
When the environment affects choices, one decision does not have to carry the whole change. Shift attention to what is visible, what is quick to get, when tiredness affects you and what solutions home or work make easy.
Understanding does not remove choices, but it can make them less mysterious. You can ask which situation is guiding eating and what in the environment reinforces a familiar habit. Then you can explore change in a way that fits real life.