**Chap­ter 6: The Cri­sis of Abun­dance**

This chap­ter delves into the mis­match between our ancient genes and mod­ern diet, high­light­ing a con­di­tion com­mon­ly unseen but preva­lent: non­al­co­holic fat­ty liv­er dis­ease (NAFLD) and its advanced form, non­al­co­holic steato­hep­ati­tis (NASH). These con­di­tions have surged along­side obe­si­ty and hyper­lipi­demia, often fly­ing under the radar due to their asymp­to­matic nature in ear­ly stages. Ini­tial­ly spot­ted in indi­vid­u­als con­sum­ing exces­sive amounts of fruc­tose-laden bev­er­ages rather than alco­hol, the surge in NAFLD/NASH cas­es is linked to our genet­ic pre­dis­po­si­tion to store fat—useful in our ances­tral past for sur­viv­ing famines but mal­adap­tive in today’s world of caloric abun­dance.

The dis­cus­sion then moves to an over­ar­ch­ing epi­dem­ic of meta­bol­ic dis­or­ders, with insulin resis­tance at the crux—a con­di­tion lead­ing not just to type 2 dia­betes but sig­nif­i­cant­ly increas­ing the risks of car­dio­vas­cu­lar dis­eases, can­cer, and Alzheimer’s. This points to a broad­er real­iza­tion: meta­bol­ic health is cen­tral to com­bat­ing these issues, more so than obe­si­ty alone. Despite the strong cor­re­la­tion between obe­si­ty and meta­bol­ic dis­eases, the text reveals that this rela­tion­ship is not straight­for­ward. Many non-obese indi­vid­u­als also suf­fer from meta­bol­ic dis­or­ders, sug­gest­ing that the issue is not mere­ly one of excess weight but of how our bod­ies han­dle the mod­ern diet.

In explor­ing our evo­lu­tion­ary back­drop, the text artic­u­lates how our ances­tors’ adap­ta­tion to store fat from fruc­tose consumption—critical for sur­vival in times of scarcity—becomes a lia­bil­i­ty in an envi­ron­ment where sug­ary diets are com­mon. The metab­o­lism of fruc­tose is sin­gled out for its unique path­way that pro­motes fat stor­age and meta­bol­ic dys­func­tion. The author stress­es that our body’s response to excess fruc­tose, due to the lack of the enzyme uri­c­ase, explains the sharp rise in meta­bol­ic dis­or­ders, show­cas­ing a deep evo­lu­tion­ary mis­match.

The chap­ter con­cludes with a cri­tique of cur­rent med­ical prac­tices that focus too late in the dis­ease tra­jec­to­ry, under­scor­ing the urgent need for ear­ly inter­ven­tions in meta­bol­ic dys­func­tions. It sug­gests a proac­tive approach, mon­i­tor­ing var­i­ous bio­mark­ers includ­ing insulin lev­els, to address meta­bol­ic health way before the onset of dia­betes or oth­er relat­ed dis­eases. The nar­ra­tive empha­sizes that through adjust­ments in diet, exer­cise, and sleep, indi­vid­u­als have sig­nif­i­cant con­trol over their meta­bol­ic health, pro­vid­ing a hope­ful the­sis on pre­vent­ing the mod­ern epi­dem­ic of meta­bol­ic dis­or­ders and extend­ing human longevi­ty.