Metabolic Rate

Metabolic rate is the speed of electron flow through the electron transport chain, the rate of oxygen consumption, and the efficiency of oxidative phosphorylation, not merely the static level of ATP produced. 3 Peat argued that the very act of respiring intensely—the high metabolic rate, the rapid electron flow, the high oxygen consumption—is what keeps cells healthy, with ATP as a necessary byproduct rather than the primary mediator. 3 This framing positions metabolic rate as the fundamental determinant of cellular readiness and health, directly opposing mainstream views that focus exclusively on ATP levels. 3

The metabolic rate is very closely related to thyroid hormone function, but defining and measuring it requires awareness of its complexity. 7 Peat observed that from puberty to old age, oxygen consumption decreases by about 70% unless intervention occurs, a decline corresponding to the increase in mortality. 8 He cited G.W. Crile's global studies showing that people in very different traditional cultures had basal metabolic rates about 30% higher than the average American, and that Crile believed the brain represented the basal metabolic rate. 8 A simple set of self-diagnostics—pulse rate and underarm body temperature taken in tandem—can estimate the current status of the metabolic rate, thyroid health, and the ability to produce energy. 2 Additional indicators include the amount of water and calories disposed of in a day, and the rate of carbon dioxide production. 7 Those with suppressed metabolic rates usually have low pulse rates (50-70 beats per minute), may exhibit cold extremities, and can suffer from a host of maladies including constipation, anxiety, depression, and poor sleep. 2

Peat's perspective inverts the conventional "rate-of-living" theory of aging. Within a given species of bird or mammal, a higher rate of metabolism is often associated with a higher body temperature and a long life span. 9 Comparing animals of different species of similar sizes, those with the highest metabolic rate are likely to have the longest average and maximum lifespans. 9 A study of 18 strains of mice found a clear association between a higher metabolic rate and greater longevity. 2 Peat noted that birds generally live longer than mammals of the same weight, though their body temperature is several degrees warmer, and that parrots with relatively large brains have an extremely long life span compared to mammals of the same body size. 2 The apparent paradox of small animals having high metabolism but short lifespans is explained by surface-area-to-mass ratios: most of a mouse's metabolic energy is spent simply maintaining its body temperature, whereas larger animals spend relatively little energy on temperature regulation. 9 The end product of respiration, carbon dioxide, is an essential component of the life process, and the ability to produce and retain enough carbon dioxide is as important for longevity as the ability to conserve enough heat. 9

A high metabolic rate, characteristic of a healthy young adolescent, is described as an oxidative metabolism in which glucose is broken down in the presence of oxygen, and healthy mitochondria produce energy and carbon dioxide. 12 Peat argued that if we optimize the known factors which improve energy production—red light, short-chain and medium-chain saturated fats, and pregnenolone, for example—to the extent that our metabolism resembles that of a ten-year-old child, there is no reason to suppose we would not have the regenerative, healing abilities common at that age. 1 This youthful, high-energy state is contrasted with the decline driven by stress hormones. Roddy and Dinkov have emphasized that a high pulse and temperature can sometimes be driven by adrenaline and cortisol rather than thyroid, making it crucial to distinguish between a truly oxidative metabolism and a stress-driven one. 10 Dinkov notes that if waking temperature is not at least 97 to 98 degrees and waking pulse is not at least 75 to 80 beats per minute, thyroid function is likely suboptimal. 11

Improving a suppressed metabolic rate involves removing metabolic inhibitors from food, particularly PUFA and phyto-/xeno-/synthetic estrogens, and supporting the cell's ability to produce energy efficiently. 2 Peat demonstrated that a high-sugar diet with adequate calcium increased carbon dioxide production and brought a previously subnormal metabolic rate up almost to normal, noting that the liver needs sugar to convert thyroxine into the active T3 hormone. 6 Progesterone supports oxidative energy and opposes all of the effects of estrogen, while serotonin inhibits oxidative energy and increases cortisol, estrogen, and prolactin. 5 The metabolic rate is thus not a fixed trait but a modifiable state reflecting the organism's capacity for generative energy, an inherent ability to produce energy that can be suppressed anytime stress is encountered. 2