Macros for Maintenance — Women Age 30-34 (Low-Carb)
For a woman aged 30-34 who is looking to hold body weight steady while supporting training and everyday energy needs, the numbers on this page are: 2139 kcal a day, split into 107 g of protein, 106 g of carbohydrate and 143 g of fat. That is the headline result, and everything below shows how it was worked out — the basal metabolic rate from the Mifflin-St Jeor equation (Mifflin et al. 1990), the activity multiplier, the goal adjustment, and the Atwater energy values of 4 kcal per gram of protein, 4 kcal per gram of carbohydrate and 9 kcal per gram of fat (Atwater 1896; USDA).
The worked example assumes a woman aged 32 weighing 67 kg and 165 cm tall, moderately active — that means exercise or active work on most days, the 1.55 activity multiplier. Those are assumptions for illustration, stated plainly so you can see exactly where every number comes from. Your own weight, height, age and activity level will give different numbers, and the Macro Calculator will work them out for you in seconds.
A macro split is only useful if it is built on a calorie target that fits the goal. A cutting split at maintenance calories will not cut anything, and a bulking split at a deficit will not build anything. So this page starts with the calories, then splits them — in that order, because the order is the whole logic of the thing.
Use the macro calculator for your own numbers
The figures here are for one specific person: a woman aged 30-34, 67 kg, 165 cm, moderately active, maintenance. To get your own split, use the Macro Calculator — enter your weight, height, age, sex, activity level and goal, and it returns your calorie target and your protein, carbohydrate and fat in grams. If you want to check the protein figure separately, the Keto Macro Calculator works it out from your body weight and activity alone.
Related macro pages covering the same calculation for other ages and diet styles:
- Macros for Maintenance — Women Age 30-34 (Balanced)
- Macros for Maintenance — Women Age 30-34 (High-Protein)
- Macros for Maintenance — Women Age 18-24 (Balanced)
The formulas, shown and cited
Two published systems do the work on this page. The first is the Mifflin-St Jeor equation for basal metabolic rate (Mifflin et al., American Journal of Clinical Nutrition 1990), which estimates the calories you burn at complete rest:
Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
The second is the Atwater system (Atwater 1896; USDA), which gives the energy in food:
Protein: 4 kcal per gram · Carbohydrate: 4 kcal per gram · Fat: 9 kcal per gram
Worked through for this page's assumed woman (67 kg, 165 cm, age 32):
- BMR = 10 × 67 + 6.25 × 165 − 5 × 32 − 161 = 1380.25 kcal a day at rest
- TDEE = BMR × 1.55 (moderately active) = 1380.25 × 1.55 = 2139 kcal a day
- Goal adjustment (maintenance): 2139 + 0 = 2139 kcal a day
The safety floors apply here and are respected: the target of 2139 kcal is above the minimum safe intake of 1,200 kcal a day for women. No target on this page ever goes below 1,200 kcal a day for women or 1,500 kcal a day for men, and nobody should eat below those floors without medical supervision.
The macro split, with the maths shown
Protein is set first, from body weight, because the evidence on protein is the strongest part of sports nutrition. For maintenance, the target used here is 1.6 g per kilogram of body weight per day, which sits at the bottom of the published range of 1.6–2.2 g/kg for lifters and dieters (Morton et al. 2018) — and above the 0.8 g/kg that covers sedentary adults. At 67 kg, that is 1.6 × 67 = 107 g of protein a day, worth 107 × 4 = 428 kcal.
Then the remaining calories are split according to the diet style. This page uses a low-carbohydrate split, with protein set first, carbohydrate capped at 20% of calories and the rest from fat: 20% of total calories to carbohydrate, with fat taking everything left after protein and carbohydrate.
| Macro | Grams per day | kcal per day | % of calories |
|---|---|---|---|
| Protein | 107 g | 428 kcal | 20% |
| Carbohydrate | 106 g | 424 kcal | 20% |
| Fat | 143 g | 1287 kcal | 60% |
| Total | — | 2139 kcal | 100% |
Check the arithmetic: 428 + 424 + 1287 = 2139 kcal, which matches the 2139 kcal target exactly. If those numbers ever disagree on a page like this, the page is wrong — the grams and the calories must always reconcile through the 4/4/9 Atwater values, and on this page they do.
Low-carb is the style to pick when you prefer rich, savoury meals and do not mind smaller portions of bread, rice and potatoes. It is not a ketogenic diet — at 20% of calories from carbohydrate there is still room for fruit, vegetables and some starchy food — and it is a preference, not a metabolic shortcut: the calorie total, not the carbohydrate total, is what drives the result.
Note what the split does not do: it does not tell you which foods to eat, and it does not say anything about food quality. 107 g of protein from chicken, lentils and Greek yoghurt is not the same diet as 107 g of protein from processed meat, even though the macro table looks identical. The numbers are a framework; the food choices inside the framework are where health actually lives.
How this split compares with the other diet styles
The same 2139 kcal can be split three ways, and the table below shows all three at this page's calorie target, so you can see exactly what changes when the style changes. The protein figure moves with the style — the high-protein style sets it at the top of the evidence range — while the carbohydrate and fat figures absorb the difference.
| Diet style | Protein | Carbs | Fat | Total |
|---|---|---|---|---|
| Balanced | 107 g | 259 g | 75 g | 2139 kcal |
| High-Protein | 134 g | 241 g | 71 g | 2139 kcal |
| Low-Carb ← this page | 107 g | 106 g | 143 g | 2139 kcal |
The comparison is worth reading carefully, because it shows that the styles are closer than their names suggest. The balanced and high-protein splits differ mainly in protein and carbohydrate; the low-carb split differs mainly in fat, which has to rise a long way to replace the carbohydrate calories at 9 kcal a gram. None of the three is "correct" in the abstract — the right one is the one whose foods you will actually keep eating for months at 2139 kcal with 107 g of protein. If you are choosing between them, try the balanced split first: it is the easiest to follow, and you can move to high-protein or low-carb from there if a specific problem — hunger, or a preference for richer food — points that way.
What a day of eating looks like
Split across four meals, the daily targets divide roughly as follows. These are illustrative portions for a woman eating 2139 kcal — adjust the foods to your own preferences, allergies and budget, and keep the totals, not the specific dishes.
| Meal | Protein | Carbs | Fat |
|---|---|---|---|
| Breakfast | 27 g | 27 g | 36 g |
| Lunch | 27 g | 27 g | 36 g |
| Dinner | 27 g | 26 g | 36 g |
| Snack / post-training | 26 g | 26 g | 35 g |
In practice, an even split across meals is a starting point rather than a rule. Many people prefer a larger dinner and a lighter breakfast, or a bigger post-training meal, and that is fine — the daily total is what drives the result, not the per-meal symmetry. Two things do matter at the meal level, though. First, spreading protein across three to five meals of roughly 25–50 g each uses it better than eating most of it in one sitting — at 27 g of protein at breakfast, this page's plan already does that. Second, the meal after training is the one worth planning properly, with protein and carbohydrate together, rather than leaving it to chance.
Foods that make these numbers easy to hit: For protein and fat, eggs, oily fish, chicken thighs, cheese, nuts, seeds, avocado and olive oil; for the carbohydrate allowance, above-ground vegetables, berries and a small portion of potatoes or oats. A single tablespoon of olive oil adds about 14 g of fat and 120 kcal, which is why fat targets are so often overshot by accident — cooking oil is invisible in the macro count unless you measure it.
How to use the result, and when to adjust it
Follow this split for two to three weeks and track your weight, then judge it by the trend, not by a single weigh-in. For maintenance, success looks like holding weight steady within a kilogram or two over several weeks. Weigh yourself at the same time of day, in the same conditions, several times a week, and look at the weekly average — daily weight moves by a kilogram or more with water, food and glycogen, and none of that is fat.
If the trend is moving up or down by more than a kilogram or two over three weeks, adjust calories by 100–200 kcal a day in the opposite direction and hold for another two weeks. Do not change the calories, the protein and the training all at once, because then you will not know which change did the work. And do not chase the scale daily — the trend over three weeks is the measurement; a single morning's number is noise.
When you do adjust, keep the same low-carb style and move the calories by 200 kcal, which changes the grams like this:
| Daily calories | Protein | Carbs | Fat |
|---|---|---|---|
| 1939 kcal | 107 g | 101 g | 123 g |
| 2139 kcal ← this page | 107 g | 106 g | 143 g |
| 2339 kcal | 107 g | 120 g | 159 g |
Age matters to the adjustment, and this page's age band is part of the calculation, not decoration. By the early thirties, most people notice that weight gained is a little harder to lose than it was at 21, and the equation agrees: basal metabolic rate falls by about 5 kcal a day for each year of age, all else equal. That is a small change — roughly 55 kcal a day between 21 and 32 — but it adds up if food and activity stay exactly as they were. Protein and resistance training matter more now than they did a decade ago, because muscle is what keeps the metabolic rate up. Women's average basal metabolic rate is lower than men's at the same age, mainly because of typically lower body weight and muscle mass — the equation captures that with the −161 constant and the weight term, not with any assumption about willpower or appetite. Around and after menopause many women notice weight settling differently; the calorie maths does not change, but resistance training and protein become more important for keeping muscle.
If you are maintenance and you train, keep the protein where it is and adjust carbohydrate and fat first when calories need to change. Cutting protein to save calories is the most common mistake in a diet, because it is muscle that gets lost alongside the fat. The protein figure of 107 g is the floor of this plan, not a negotiable extra.
What the macro numbers do NOT tell you
A macro split is an estimate built on an estimate. The Mifflin-St Jeor equation predicts basal metabolic rate for a population average, and any individual can sit 10–15% above or below it. The activity multiplier of 1.55 is a broad band, not a measurement — two people who both describe themselves as "moderately active" can burn very different amounts in a day. That is why the page tells you to track the weight trend and adjust, rather than treating 2139 kcal as a precise prescription.
The split also says nothing about micronutrients, fibre, or food quality. It is entirely possible to hit 107 g of protein, 106 g of carbohydrate and 143 g of fat while eating almost no vegetables, almost no fibre, and far too much salt and added sugar. The numbers are a calorie framework, not a complete diet. A useful rule of thumb alongside them: aim for at least 25–30 g of fibre a day and a plate that is half vegetables at lunch and dinner, and the micronutrient side of the diet largely takes care of itself.
The split also cannot account for medical conditions. Kidney disease changes the protein answer — people with reduced kidney function should not follow a high-protein target without a clinician's guidance. Diabetes changes the carbohydrate answer. A thyroid condition, certain medications, pregnancy and breastfeeding all change the calorie answer. This page is a general-purpose estimate for a healthy adult; if any of those apply, the numbers here are a starting point for a conversation with a professional, not a plan to follow alone.
Finally, the split does not measure adherence. The best macro ratio in the world is worthless if the diet is miserable enough to abandon in a fortnight. If this split feels unworkable — if training feels flat without carbohydrate, or the fat level is hard to enjoy — change the split and keep the calories and the protein, rather than abandoning the plan altogether.
Frequently asked questions
How many calories should a woman aged 30-34 eat for maintenance?
On the assumptions used here (67 kg, 165 cm, moderately active), the estimate is 2139 kcal a day — a basal metabolic rate of 1380 kcal times the 1.55 activity multiplier, giving a maintenance level of 2139 kcal, with no adjustment. Your own figure will differ with your weight, height and activity; use the Macro Calculator with your own numbers.
How much protein is 107 g a day in real food?
About four servings of 25–50 g of protein — for example, a chicken breast (about 30 g), a pot of Greek yoghurt (about 20 g), two eggs with beans (about 20 g) and a portion of lentils or fish (about 25 g). The point of the per-meal table above is that 107 g sounds like a lot as one number and is very manageable split across four meals of roughly 27 g each.
Will I feel flat training on 106 g of carbohydrate a day?
Possibly, at first. At 106 g of carbohydrate a day — 20% of 2139 kcal — there is less quick fuel available for hard sessions than on a balanced split, and some people notice a dip in high-intensity performance for the first one to two weeks while the body adapts. If training suffers, the practical fix is to put most of the day's carbohydrate in the meal before and the meal after training, and to judge the split after two to three weeks rather than after three days. If performance is still down, the balanced split at the same 2139 kcal is the better choice — the calories, not the carbohydrate, decide the result.
Should I count macros every day?
Counting is most useful as a learning tool. Two to four weeks of tracking teaches you what 107 g of protein and 106 g of carbohydrate actually look like on a plate, and after that many people can eat to the same pattern without weighing everything. If tracking becomes stressful or obsessive, stop — the numbers are a tool, not a test, and a relaxed eater who roughly follows the pattern will outperform a stressed eater who tracks perfectly for a month and then quits.
Why is the protein target 1.6 g/kg instead of 0.8 g/kg?
The 0.8 g/kg figure is the minimum to avoid deficiency in a sedentary adult, not the amount that best supports training and maintenance. The published evidence for active people (Morton et al. 2018) supports 1.6–2.2 g/kg for lifters and dieters, and this page uses 1.6 g/kg — inside that range. One exception: kidney disease changes the answer, so anyone with reduced kidney function should check with a clinician before following a high-protein target.
What if my weight does not change after three weeks on 2139 kcal?
First, check the trend rather than a single weigh-in — daily weight fluctuates by a kilogram or more. If the three-week average is genuinely flat, adjust calories by 100–200 kcal in the direction of your goal (down if cutting, up if bulking) and hold for another two weeks before judging again — the adjustment table above shows the grams at 1939 and 2339 kcal. Also check the quiet calorie leaks: cooking oil, drinks, sauces and snacks are the usual reason a careful-looking diet is not actually at 2139 kcal.
Related pages
Estimates only, not medical advice. Minimum safe intakes: 1,200 kcal/day women, 1,500 kcal/day men — consult a healthcare professional before a very-low-calorie diet.