Appendix G — Special Populations Quick Reference

⚠️ This appendix summarizes what CHANGES for particular groups. It does not replace the chapters, and for anything clinical it does not replace a clinician.

⚠️ Chapter 37 §37.5 lists the eight things that genuinely differ between people. This is that list, expanded into what each one actually changes.


⚠️ How to use this

⚠️ The default recommendation is Chapter 37 §37.3's plate. Every entry below is a MODIFICATION of it, not a replacement.

⚠️ In most cases the modification is smaller than people expect — Walt Prosser's diabetes changed his targets, his monitoring and his stakes, and barely changed his food (Ch 37 CS2).

⚠️ And two of these groups need the general advice INVERTED — more energy, more density, eat enough. Those are marked ⚠️🔄 and they are the ones most often got wrong.


Pregnancy and preconception

Chapter 25.

⚠️ What changes
⚠️ Folic acid ⚠️ Supplement preconception and early pregnancy. ✅ — one of the clearest in the book
⚠️ Iodine ⚠️ Requirement rises; a genuine and under-recognized gap
⚠️ Iron ⚠️ Requirement rises substantially
Vitamin D ⚠️ Commonly supplemented
⚠️ Vitamin A ⚠️ AVOID high-dose retinol and liver — teratogenic
⚠️ Alcohol ⚠️ No established safe level
Food safety ⚠️ Listeria and toxoplasma precautions; national guidance is specific and worth reading
Energy ⚠️ Rises modestly, and much less than "eating for two" implies

Lactation

Chapter 25.

⚠️ Energy and fluid requirements rise · iodine and B12 matter for the infant · and Chapter 25 gave BOTH halves: breastfeeding has real benefits AND the pressure around it causes documented harm.

⚠️ The maternal diet does not need to be restricted in the way it is popularly assumed to.

Infants and young children

Chapter 25.

⚠️ Iron from around six months · vitamin D commonly supplemented · no honey under one year · no low-fat approaches in the very young · and salt kept low.

⚠️ Allergen introduction: current guidance in several countries favours EARLY introduction rather than avoidance (Ch 28) — ⚠️ a reversal from previous advice and worth checking nationally.

Children and adolescents

Chapters 25 and 33.

⚠️ The feeding relationship matters more than the composition
⚠️ Restriction of a food ⚠️ Increases wanting and unsupervised consumption (Ch 33 §33.6b)
⚠️ Pressure toward a food ⚠️ Reduces liking for it, for years
⚠️ Food as reward ⚠️ Raises the reward food's value and lowers the meal's
⚠️ The division of responsibility ⚠️ Adult decides what, when, where. Child decides whether and how much
⚠️ Calcium and adolescence ⚠️ Peak bone mass is laid down here and cannot be fully recovered later (Ch 25 §25.10b)
⚠️ Adolescent energy needs ⚠️ Large and rising. Under-eating is the more common problem in this group than over-eating

⚠️ And no moral vocabulary about food in front of children (Ch 34 §34.11). ⚠️ A great deal of adult disordered eating was installed with the best of intentions.

Older adults ⚠️🔄

Chapters 25, 29. ⚠️ Much of the general advice inverts here.**

⚠️ What changes
⚠️ Protein ⚠️ Requirement RISES — muscle protein synthesis is less responsive. ~1.2–1.5 g/kg
⚠️ Energy density ⚠️ Becomes a FEATURE, not a problem. Appetite falls and volume crowds out intake
⚠️ Fibre ⚠️ Titrated rather than maximized
B12 ⚠️ Absorption falls; supplementation commonly indicated
Vitamin D and calcium ⚠️ Bone and fall risk
⚠️ Hydration ⚠️ Thirst sensation is less reliable
⚠️ Isolation ⚠️ A major driver of poor intake. Company is an intervention (Ch 33 §33.9b)
⚠️ Unintentional weight loss ⚠️ A red flag, not a success (Ch 29, Ch 34)

⚠️ Gerard Mbeki is this row. ⚠️ Every default assumption in ordinary dietary advice was wrong for him, and what helped most was a lunch club.

Athletes and heavy training

Chapters 23, 34.

⚠️ Energy availability first, before anything else · carbohydrate periodized to training load · protein 1.6–2.2 g/kg · iron status monitored, particularly in endurance and in menstruating athletes · sweat rate measured individually (App B §8) · ⚠️ and the five supplements with real evidence: creatine, caffeine, beta-alanine, nitrate, bicarbonate.

⚠️ RED-S (Ch 34 §34.6): ⚠️ occurs in all sexes at every level, does NOT require a low body weight, and amenorrhoea is a symptom rather than a sign of training hard enough.

⚠️ Chapter 23 §23.13 refused body-composition targets deliberately, and Chapter 34 explains why.

Vegetarian and vegan diets

Chapters 8, 13, 14, 19.

⚠️ Nutrient ⚠️ What to do
⚠️ B12 ⚠️ Supplement or reliably fortified foods. Not optional for vegans
Iron ⚠️ Non-haem absorption is lower; vitamin C at the same meal helps
Iodine ⚠️ Frequently low; check plant milks are fortified
Calcium ⚠️ Fortified alternatives, and check the specific product
⚠️ Omega-3 ⚠️ ALA from walnuts and flax; conversion to EPA/DHA is limited. Algal oil is the direct option
Protein ⚠️ Adequate with variety and sufficient total intake; pulses do most of the work
Zinc, selenium ⚠️ Worth attention

⚠️ Chapter 36 §36.9: this is also close to the environmentally recommended pattern, which is the convergence Chapter 37's threshold rests on.

Diagnosed food allergy

Chapter 28. ⚠️ The one absolute personalization in this book.**

⚠️ Strict avoidance of the diagnosed allergen · adrenaline auto-injector carried and in date · an anaphylaxis plan · label vigilance at every purchase (Ch 30) · ⚠️ and "may contain" does not indicate a graded level of risk.

⚠️ IgG "food sensitivity" panels are ❌ and generate eliminations that do harm (Ch 28, Ch 35).

Coeliac disease and gluten

Chapter 28.

⚠️ TEST BEFORE REMOVING GLUTEN. ⚠️ Testing requires gluten in the diet, and removing it first makes diagnosis substantially harder. This is the single most consequential procedural point in Chapter 28.

⚠️ Confirmed coeliac disease: strict lifelong gluten avoidance, plus monitoring for iron, B12, folate, calcium and vitamin D. ⚠️ NCGS is real, is not coeliac disease, and fructans may explain a substantial share of it.

Type 2 diabetes and prediabetes

Chapter 26.

⚠️ The dietary pattern is Chapter 37's plate · glycaemic control IS a treatment target here and is not for most readers (Ch 35 §35.2) · ⚠️ weight loss has a dose–response relationship with remission (DiRECT) · metformin and B12 monitoring (Ch 16) · ⚠️ and a CGM is genuine care in this group.

Cardiovascular disease and lipids

Chapters 9, 19, 26.

⚠️ LDL-C is a settled causal target · the saturated-fat question is about the REPLACEMENT (Ch 9's substitution rule) · ⚠️ less processed meat · oily fish · fibre, particularly viscous fibre and psyllium · and sodium (Ch 15, 36).

Kidney disease and other clinical diets

Chapters 26, 29.

⚠️ These are prescribed, individualized and monitored. This appendix will not summarize them and a book should not.

⚠️ Chapter 29's inversions are the general warning: restriction that is correct in one patient is harmful in another, and the undernourished are the group most often harmed by well-intentioned restriction.

Undernutrition and clinical malnutrition ⚠️🔄

Chapters 29, 34. ⚠️ Everything inverts.**

⚠️ REFEEDING SYNDROME ⚠️ Reintroducing nutrition after substantial undernutrition shifts phosphate, potassium, magnesium and fluid, and can be fatal
⚠️ Therefore ⚠️ Nutritional restoration in the significantly unwell is a MONITORED MEDICAL PROCEDURE
⚠️ And ⚠️ Energy density is a feature; restriction is a harm; "healthy eating" advice is actively wrong here

⚠️ One of only two places in this whole book where following general nutrition advice could kill someone.

Eating disorders

Chapter 34.

⚠️ This appendix will not give a modification, because the modification is not dietary.

⚠️ Most people with eating disorders are not underweight. Duration of untreated illness predicts outcome. There is no threshold you have to reach.

⚠️ Chapter 34 §34.14 has the help information, and Chapter 37 §37.10 says plainly that the plate is not the intervention.

Food insecurity

Chapter 32.

⚠️ Not a special population in the clinical sense and it belongs here because it changes what advice is usable more than most diagnoses do.

⚠️ Cash flow and income are different constraints · bulk buying requires capital · the cheapest calories and cheapest nutrients are different foods · assistance take-up is consistently below eligibility (Ch 32 §32.8) · ⚠️ and involuntary restriction runs the same physiological cycle as voluntary restriction (Ch 33 §33.6, Ch 34 §34.10).


⚠️ The cross-cutting rule

⚠️ Two of the groups above need MORE — more energy, more density, more protein, eaten more often: older adults, and anyone undernourished or recovering.

⚠️ General dietary advice is written for neither, and is frequently harmful when applied to them.

⚠️ If you are advising someone, establish which direction they need before you say anything.

⚠️ Chapter 33 §33.3's diagnostic generalizes: ask what is actually happening before choosing the tool, because using the wrong one is worse than doing nothing.