Why Calorie Counting Isn’t Always Accurate — Especially for Women with PCOS

If you’ve ever found yourself hesitating to add a handful of nuts to your lunch, a drizzle of olive oil to your salad, or a slice of avocado to your breakfast because you’re worried about the calories—you’re not alone. Many women I work with, especially those navigating PCOS, have a long history with calorie counting. But here’s the truth: not all calories are created equal.

In this post, we’ll break down why calorie counting isn’t the most accurate way to track your food intake, how your body really processes different foods, and why it’s time to rethink your fear of healthy fats.

What Calorie Counting Gets Wrong

The basic idea of "calories in vs. calories out" assumes that all calories are processed the same way by the body—but they’re not. The number you see on the back of a food label is a rough estimate based on historical data, and it doesn’t account for:

• How much energy is required to digest that food

• How fully your body absorbs it

• The hormonal and metabolic impact of the nutrients inside it

  
  

So while it might seem like adding a tablespoon of peanut butter (approx. 100 kcal) is "too much," your body doesn’t treat those 100 calories the same as it would 100 calories from a biscuit.

The Thermic Effect of Food (TEF): Calories Used to Digest

Some foods actually burn more calories to digest and absorb than others. This is known as the thermic effect of food (TEF).

• Protein-rich foods (like chicken, eggs, tofu): up to 20–30% of the calories consumed may be burned just digesting them.

• Fibrous carbohydrates (like vegetables, legumes, and whole grains): generally have a TEF of around 10%, but it can be higher depending on the food's complexity.

• Fats: have a much lower TEF—just 0–3% of their energy is used for digestion.

  
  

In practical terms, this means that the same calorie total from different foods can result in very different net energy gains. For example, a meal rich in whole grains and protein may burn significantly more calories during digestion than a processed, low-fibre, high-fat alternative—even if they contain the same number of calories on paper.

For women with PCOS, this matters even more. Studies suggest that insulin resistance—which affects many women with PCOS—can reduce the thermic effect of food by 50–150 kcal per day, making calorie math even less predictable.

Not All Calories Are Absorbed

Another important factor? Not every calorie you eat is fully absorbed.

Foods high in fibre or resistant starch (like beans, seeds, and whole grains) often pass through your digestive system partially undigested:

• Whole flaxseeds can pass through the gut almost entirely intact unless ground first, meaning some of their calories are never absorbed.

• Whole nuts (like almonds) have been shown to deliver up to 25% fewer absorbable calories than predicted by food labels due to their fibrous cell walls.

• Legumes and whole grains contain resistant starch that ferments in the large intestine rather than being fully digested, resulting in 5–10% fewer net calories than expected.

  
  

So yes, that slice of seeded wholegrain bread might technically have more calories than white toast—but you won’t necessarily absorb them all, and you’ll benefit from slower blood sugar release, better gut health, and longer-lasting energy.

Healthy Fats: Calorie-Dense but Nutrient-Rich

Fat has gotten a bad reputation, mainly because it’s the most calorie-dense macronutrient (9 kcal per gram). But in reality, healthy fats are essential for hormone balance, brain function, and sustained energy—especially for women with PCOS.

When clients ask me if a tablespoon of olive oil or a few slices of avocado will "mess up their progress," I remind them:

• These foods are anti-inflammatory and help regulate cycles

• They help keep you full for longer

• They support the absorption of key nutrients (like vitamins A, D, E, and K)

  
  

Plus, the body uses very little energy to digest fat (low TEF), but the benefits go far beyond calories. Fat-rich foods often support hormone health and satiety in ways that help women feel more in control of cravings and cycles long-term.

A Better Way to Think About Nourishment

Instead of asking, “How many calories is this?” try asking:

• “Will this keep me full and satisfied?”

• “Will this help balance my blood sugar?”

• “Is this food supporting my hormones, energy, or mood?”

  
  

Food is more than maths. It’s nourishment, pleasure, and information for your body.

And if you’ve been stuck in a calorie-counting mindset for years, it’s okay to start slowly. Begin by adding, not restricting: add some seeds to your breakfast, some olive oil to your veggies, some hummus to your snack plate.

Small changes, made consistently, are what drive big shifts.

Ready to Ditch the Numbers?

If you’re tired of obsessing over calories and want to learn how to nourish your body without fear, I’d love to help. Book a free discovery call to learn how we can work together to reduce symptoms and feel more in control of your health—without restriction.