# Vegan and Not Eating Enough: The Hidden Calorie Gap

How a plant-based plate quietly under-feeds women, the signs of low energy availability, the numbers, and the dense foods that close the gap in a week.

By Barbara · 2026-10-22 · https://veganbutstilltired.com/gaps/vegan-not-eating-enough-calories-fix

This is the gap that hides best, because it looks like success. The plate is enormous, green, photographed. The woman eating it is cold, tired, waking at four, losing hair, has not had a proper period in months, and has been told by everyone that she is doing everything right. She is eating 1,300 kilocalories a day and training five times a week. Plants are mostly water and fibre; a kilo of vegetables carries less energy than a handful of nuts. Unless a plant-based plate is built deliberately around dense foods, it under-feeds, and the body responds by turning down everything it can spare: temperature, hormones, mood, repair.

## The signs you are not eating enough

- Cold all the time; cold hands, cold feet, a low body temperature in the morning.
- Hungry at night and not hungry in the morning; waking at three or four and not getting back.
- Periods that became light, irregular or stopped; low libido.
- Training that stopped progressing months ago; a resting heart rate that drifts down and a mood that drifts with it.
- Hair shedding, constant thoughts about food, a plate that must be "clean" to feel acceptable.
- Weight that has stalled or crept up despite eating "so little", because the body has slowed to match.

In women who train, this pattern has a name, low energy availability, and it is defined by numbers, below.

## The numbers

| Measure | Figure |
|---|---|
| Typical energy need, woman 55 to 70 kg, moderately active | 1,800 to 2,200 kcal a day |
| With daily training | 2,200 to 2,600 kcal a day |
| Energy availability (intake minus training energy, per kg of fat-free mass) | below 30 kcal per kg is low; 45 kcal per kg is healthy |
| What 1 kg of mixed vegetables carries | about 250 to 400 kcal |
| What 100 g of mixed nuts carries | about 600 kcal |

Worked example: a 65 kg woman with 48 kg of fat-free mass who eats 1,500 kcal and burns 400 kcal in a run has an energy availability of (1,500 minus 400) divided by 48, which is 23 kcal per kg. Her body reads that as famine and behaves accordingly.

There is no blood test for this gap. The three-day weighed log, an honest count of training, and the arithmetic above are the test, and they are more reliable than any marker.

## The foods that close the gap without a bigger plate

Density is the whole game. Add fat, add nuts and seeds, add the foods you were avoiding because they were "calorie-dense", which is precisely the quality you need.

| Food | Portion | Energy | How to use it |
|---|---|---|---|
| Mixed nuts | 40 g | 240 kcal | a handful mid-morning, every day |
| Tahini | 30 g | 180 kcal | stirred into dressings, over roasted roots |
| Peanut or almond butter | 30 g | 180 kcal | on the morning oats, on apple slices |
| Extra virgin olive oil | 1 tablespoon | 120 kcal | over everything that is already cooked; three a day |
| Avocado | half | 160 kcal | on toast, in the bowl |
| Oats, dry | 80 g | 300 kcal | porridge made with soy milk, not water |
| Dried fruit (dates, apricots, figs) | 50 g | 140 kcal | in the oats, after training |
| Soy milk | 500 ml across the day | 230 kcal | the kettle-side habit |
| Tofu, firm | 200 g | 290 kcal | the dinner anchor |
| Hummus | 100 g | 250 kcal | with everything |
| Dark chocolate | 30 g | 170 kcal | because joy is also a nutrient |
| Granola with nuts | 60 g | 280 kcal | over plant yoghurt |

Two tablespoons of olive oil, a handful of nuts, a spoon of tahini and soy milk in place of water in the porridge add about 700 kcal to a day without adding a single extra plate.

## The rules

**Eat breakfast within an hour of waking,** and make it the densest meal: oats with soy milk, nut butter, seeds and fruit is 600 kcal that sets the day's appetite straight.

**Add fat to every cooked meal after it is cooked.** Oil, tahini, nuts, avocado. This is the lever with the largest effect per effort.

**Cap the fibre.** Above about 50 g a day, fibre fills you before you have eaten enough; most under-fed vegans are at 60 to 70. Swap some raw vegetables for cooked, some beans for tofu, some wholegrain for white rice on training days.

**Fuel the training.** 30 to 60 g of carbohydrate in the hour before and a real meal within two hours after; a banana and a date before, the lentil bowl after.

**Stop the "clean" rule.** Energy from a flapjack is energy. A plate that must be perfect is a plate that is usually too small.

**Watch the period, not the scale.** A regular cycle is the clearest sign that a woman is eating enough; its absence is the clearest sign she is not. If it has been gone for three months, this is the gap to close first, and a clinician should know.

## The one-week fix

1. Log three days, weighed, and run the arithmetic above once. You will not need to do it again.
2. Make porridge with soy milk and a spoon of nut butter every morning this week.
3. Add a tablespoon of olive oil or tahini to lunch and dinner after cooking.
4. Put a bag of mixed nuts in the bag you carry; eat a handful at eleven and at four.
5. Keep training, but eat a date and a banana before and the lentil bowl after, every session.
6. Expect warmth within days and sleep within two weeks. The period and the training progress follow over two to three months.

## What the research says

- The evidence file behind this site, gaps-fatigue-v1, draws on the EFSA Dietary Reference Values for energy and the International Olympic Committee consensus on relative energy deficiency in sport (Mountjoy and colleagues, British Journal of Sports Medicine, 2018), which sets the low energy availability threshold at about 30 kcal per kg of fat-free mass and lists the signs above. The contrary finding: the 30 kcal threshold comes largely from short laboratory studies in young women, and individual thresholds vary, so the signs matter more than the exact number. [doi.org/10.1136/bjsports-2018-099193](https://doi.org/10.1136/bjsports-2018-099193)

## Questions women ask

**I am trying to lose weight. Does this apply to me?** Yes, more than to anyone. A body in famine holds on to fat and sheds muscle; eating enough, with protein and strength work, is how the composition changes. A deficit of 300 to 500 kcal from a properly fed baseline works; a deficit from 1,300 does not.

**How can I be eating too little when I am always eating?** Grazing on vegetables, fruit and rice cakes is a lot of chewing for very little energy. Density, not volume, is the fix.

**Will the extra fat make me gain weight?** Adding 500 kcal to a day that was 1,300 brings you to a number your body stops fighting. Most women find the scale moves less than they feared and the energy, warmth and sleep move more than they hoped.