Most cohort data on body composition comes from American or European labs. New Zealand adults deserve a local read. After 22 years of practice and 1,380 clients passing through BIA scanning, weekly dietary review, and coached adjustment, the patterns are clear enough to publish. The short answer: the median NZ adult walking into Inception is over-fed and under-muscled, and twelve weeks of structured work moves both numbers in the right direction.

What the median NZ adult looks like on day one

The composite picture is not flattering, but it is honest. The median client arriving at the Christchurch facility for a first BIA scan is between 38 and 54 years old, carrying 8 to 14 kg of excess fat mass, and sitting 3 to 6 kg below the lean mass we would expect for their height and frame.

Three patterns repeat across the intake data:

  • Protein intake sits well below 1.6 g/kg of reference body weight. Most are eating 0.8 to 1.1 g/kg.
  • Fibre intake is between 14 and 22 g per day, against a target north of 30 g.
  • Resistance training frequency is one session per week or fewer, regardless of how active the client describes themselves.

The "active but soft" presentation is the most common phenotype. Tramping, cycling, social netball, and a physical job are not stimuli that protect lean mass after 35. Cardiovascular work is necessary. It is not sufficient.

What the dietary dataset shows

The Inception food intake dataset now sits at 2,846 foods catalogued for macros, fibre, and micronutrient density. When client food logs are mapped against it, the deficits are predictable.

Protein is the headline. The second issue is energy density disguised as health food. Granola, smoothies, dried fruit, "protein" bars, flavoured yoghurts, and store-bought salad dressings push energy intake 400 to 800 kcal above what clients estimate. The third issue is alcohol, which clients consistently under-report by 30 to 50 percent compared with what they later acknowledge in coaching.

Energy is not the enemy. Confusion about energy is.

The twelve-week median trajectory

Across the cohort, the median twelve-week trajectory looks like this when methodology compliance is reasonable (defined as logged intake four or more days per week and two resistance sessions per week):

  • Fat mass: down 4.2 to 6.8 kg
  • Lean mass: up 0.6 to 1.4 kg
  • Waist circumference: down 5 to 9 cm
  • Resting hunger ratings: down across the twelve weeks, not up

The lean mass gain matters more than the fat loss number. Most diet protocols in the public domain produce weight loss where 25 to 30 percent of the loss is lean tissue. In the Inception cohort, the median client gains lean mass while losing fat. That is a function of protein floor, resistance training prescription, and rate of loss control, not anything exotic.

The clients who hold their results at twelve months are not the ones who lost the most weight. They are the ones who added the most lean mass while doing it.

Why the local context matters

NZ-specific framing is not a marketing line. It changes the prescription.

Kūmara, mince, lamb, dairy, and seasonal stone fruit dominate the food environment here in ways they do not in the US literature. Seasonal daylight in the South Island shifts training adherence in winter. GP referral patterns for thyroid, iron, and vitamin D testing are specific to the NZ system, and we work alongside your GP rather than around them. The cohort data reflects all of that.

A handful of sub-patterns worth flagging:

  • Iron status in pre-menopausal female clients is the single most common lab flag. It limits training capacity before it limits energy.
  • Vitamin D in winter sits low across the cohort, particularly in clients south of Timaru.
  • Perimenopausal clients (roughly 42 to 54) need a different protein and training prescription than the generic "eat less, move more" advice they have been given for a decade.

These are not edge cases. They are the median.

What separates the responders from the non-responders

The cohort splits cleanly. Responders share four features:

  1. They hit a protein floor of 1.6 g/kg or higher, four days out of seven minimum.
  2. They train resistance twice per week, every week, with progression tracked.
  3. They sleep seven hours or more on at least five nights.
  4. They keep alcohol below six standard drinks per week during the twelve weeks.

Non-responders almost always fail on two or more of those four. Not on willpower. Not on metabolism. On those four inputs.

When clients ask what we prescribe in coaching beyond food and training, the supplement layer through Inception Labs is targeted at the gaps the dataset shows: protein where intake will not get there from food alone, creatine for the lean mass response, and specific micronutrient support where labs justify it. Nothing speculative. Nothing for the sake of a stack.

What the data does not say

Cohort observation is not a randomised trial. The 1,380 figure is people who chose to engage coaching and were scanned at intake and review. Selection bias is real. Clients who quit at week three are not in the twelve-week median.

What the data does say, with reasonable confidence:

  • The methodology produces lean-mass-preserving fat loss in the median NZ adult who completes the protocol.
  • The local food environment is workable. Clients do not need to import anything exotic.
  • The trajectory is repeatable across age bands from 30 to 65, with prescription adjustments.

It is first-party data. It is local. It is the basis for what we do, and it is updated as the cohort grows.

The longevity read

Lean mass is the variable that ages best. Skeletal muscle predicts function, glucose handling, fall risk, and metabolic resilience into the seventh and eighth decades. The cohort data lines up with the wider literature on this point. Adults who arrive at 45 already losing lean mass and do nothing about it are on a trajectory that gets harder to reverse every year. Adults who reverse it at 45 buy themselves a different decade at 65.

The twelve-week scan is the diagnostic. The twelve-month and three-year follow-up scans are the read on whether the work held. That is the dataset we are most interested in continuing to build.

What to do this week

  • Book a BIA scan and get a baseline rather than guessing from the bathroom scale.
  • Log three honest days of food intake, including weekends and alcohol.
  • Hit 1.6 g/kg of protein for seven days and notice what it does to hunger.
  • Add a second resistance session to the week, even a short one, and track the loads.
  • If labs have not been checked in two years, ask your GP for iron, vitamin D, and a basic metabolic panel.