Issue 6, 2013

Adjustment to dietary energy availability: from starvation to overnutrition

Abstract

Humans have evolved into efficient survivors, able to bridge periods of scarcity between times of food availability. Adaptation to these changes requires specific adaptations and the establishment of metabolic priorities. These include thermal homoeostasis, maintained tissue glucose availability and the selective utilization of energy substrates, depending on their availability. A consequence of these requirements is the necessary maintenance of body reserves of energy, largely triacylglycerols, controlled by an effective ponderostat system. Body triacylglycerol reserves are used to sustain most of the body’s energy needs in periods of scarcity. Protein, throughout evolution, has been difficult to obtain, and, as a consequence, it is not used as an energy substrate except under conditions of excess, but (also) as a source of glucose and energy. Under excess energy conditions (as found in many present-day diets), the finely tuned mechanisms to survive starvation are inadequate to eliminate this excess. Humans are essentially unprepared for sustained excess energy intake; thermogenesis, increased protein turnover, growth and lipid accretion help decrease the energy burden. However, in the long-term, excess lipid accumulation in adipose tissue elicits inflammation and immune system-derived responses that deeply affect the control of energy partition, including the ponderostat setting and the disposal of excess glucose and amino acids. These changes alter the function of white adipose tissue, muscle, liver and the intestine (including the microbiota), all subjected to a low-key inflammation condition that alters their function and elicits a number of associated diseases constituting metabolic syndrome. In summary, it is hypothesized that dietary plentifulness and the pre-established mechanisms to fight scarcity are both responsible for the development of metabolic syndrome, which can be thus defined as a disease of affluence.

Graphical abstract: Adjustment to dietary energy availability: from starvation to overnutrition

Article information

Article type
Review Article
Submitted
12 Jun 2012
Accepted
25 Oct 2012
First published
30 Oct 2012

RSC Adv., 2013,3, 1636-1651

Adjustment to dietary energy availability: from starvation to overnutrition

M. Alemany, RSC Adv., 2013, 3, 1636 DOI: 10.1039/C2RA21165C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements