The Biopsychosocial Model of Weight Loss: Is Being Overweight A Choice?

Coach Alan
Sep 16
3 min read

My perspective is somewhat that of a determinist.

In other words, I don’t believe I consciously make my own decisions. Instead, I believe they are largely influenced, if not determined, by unconscious factors.

In this post, I’ll explain how these factors shape your weight loss journey through the lens of the biopsychosocial model of weight loss. By becoming more aware of them, you can influence them, which means they can begin to work in your favour instead of against you.

What is the Biopsychosocial Model of Weight Loss?

Simply put, it’s a holistic framework developed to understand health and illness, including addiction and mental health difficulties.

It looks at how our biology, psychology, and outer (social) world interact and influence each other, and how this interaction determines our well-being and the decisions we think we’re making freely.

Everyday Examples of the Biopsychosocial Model in Action

Example 1: Social, Biological, and Psychological Triggers Behind Food Choices

Social/External World: On your way home from work, you pass your local takeaway and unconsciously catch the smell of food.

Biology: Craving-related regions in your brain are triggered

Psychology: Later, at home, a “random” thought pops up: “I’m craving a takeaway right now.”

Decision: You order a takeaway, convinced it was a conscious choice, even though the chain began earlier.

Example 2: How Social, Biological, and Psychological Factors Lead to Skipping a Workout

Social/External World: Last night, you scrolled on your phone in bed.

Biology: Your brain’s “stay alert” system was triggered, which prevented deep sleep. You woke up drained the following morning.

Psychology: Feeling low on energy, you weren’t motivated to do the workout you had planned.

Decision: You skipped the workout, again believing it was a conscious choice.

The Core Principle of Weight Loss

When it comes to losing weight, success rests on your decisions aligning with this one principle: burning more calories than you consume.

That means cutting calorie intake while improving food quality, increasing daily activity, and engaging in regular strength training.

But whether you can stay consistent with those decisions depends on how well your biology, psychology, and social world align with your goals.

Why Weight Loss Consistency is So Hard

Biological Factors That Affect Weight Loss Consistency

If your sleep quality is poor, your cravings rise, energy drops, and motivation tanks, all of which influence food and exercise decisions.

Psychological Factors That Affect Weight Loss Consistency

If your thinking patterns undermine your goals, they’ll pull you off track.

Social Factors That Affect Weight Loss Consistency

If your partner regularly orders takeaways and the house is stocked with snacks, resisting becomes much harder.

How to Use the Biopsychosocial Model to Improve Weight Loss

These three factors are not fully in your control, but they can be shaped.

Shaping Your Social World for Weight Loss Success

Improve your sleep setup.

Stop buying multipack snacks and get singles instead.

Surround yourself with people on the same journey.

Supporting Your Biology to Stay Consistent With Weight Loss

Prioritise good sleep.

Get early morning sunlight and movement.

Stay hydrated throughout the day.

Strengthening Your Psychology to Overcome Weight Loss Barriers

Practice mindfulness and self-reflection.

Test your assumptions and challenge unhelpful thinking.

Work on reframing limiting beliefs.

Final Thought on the Biopsychosocial Model of Weight Loss

You don’t control every influence on your decisions, but you’re not powerless either. The key is awareness. Awareness can help you pause and reflect before acting upon decisions. Additionally, by shaping your social world, supporting your biology, and training your mind, you stack the odds in your favour.

Weight loss then becomes less about relying on willpower and more about designing an environment and mindset where consistency becomes the natural outcome.

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