Does heaven exist? With well over 100,000 plus recorded and described spiritual experiences collected over 15 years, to base the answer on, science can now categorically say yes. Furthermore, you can see the evidence for free on the website allaboutheaven.org.

Available on Amazon
also on all local Amazon sites, just change .com for the local version (.co.uk, .jp, .nl, .de, .fr etc.)


This book, which covers Visions and hallucinations, explains what causes them and summarises how many hallucinations have been caused by each event or activity. It also provides specific help with questions people have asked us, such as ‘Is my medication giving me hallucinations?’.

Available on Amazon
also on all local Amazon sites, just change .com for the local version (.co.uk, .jp, .nl, .de, .fr etc.)

Observations placeholder

Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios



Type of Spiritual Experience


High protein depresses tryptophan, tryptophan is related to negative mood disorders.  Too much protein thus has a negative effect on mood.

A description of the experience

Am J Clin Nutr. 2003 Jan;77(1):128-32.

Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios.

Wurtman RJ1, Wurtman JJ, Regan MM, McDermott JM, Tsay RH, Breu JJ.   1Clinical Research Center, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge 02139, USA. dick@mit.edu


The delivery of circulating tryptophan to the brain and its conversion to serotonin vary directly with plasma concentrations of tryptophan and inversely with those of other large neutral amino acids (LNAAs). Although carbohydrate-rich, protein-free formula diets have been shown to elevate, and high-protein diets to depress, the tryptophan-LNAA ratio, few data are available about this ratio's responses to actual meals.


We determined whether carbohydrate-rich or protein-rich breakfasts, such as those Americans normally eat, produce substantial differences in the plasma tryptophan-LNAA ratio and in the corresponding ratio for tyrosine, the precursor of brain dopamine and norepinephrine.


Nine overnight-fasted subjects consumed, 3-7 d apart, a carbohydrate-rich (69.9 g carbohydrate and 5.2 g protein) and a protein-rich (15.4 g carbohydrate and 46.8 g protein) breakfast. Blood samples collected at baseline and after 40, 80, 120, and 240 min were assayed for tryptophan, tyrosine, the 5 other LNAAs, and insulin.


The carbohydrate-rich and protein-rich breakfasts had significantly different effects on both the plasma tryptophan-LNAA and tyrosine-LNAA ratios (each P < 0.01). Among the 8 subjects who consumed both breakfasts, the median difference for tryptophan:LNAA was 54% (range: 36-88%) and for tyrosine:LNAA was 28% (range: 10-64%). Insulin concentrations rose significantly after the carbohydrate but not after the protein meal.


High-carbohydrate and high-protein breakfasts similar to those Americans normally eat can cause substantial differences in the plasma tryptophan ratio and thus, probably, in brain tryptophan concentrations and serotonin synthesis. Such meals also change the plasma tyrosine ratio and may thereby modify catecholamine synthesis.

PMID:  12499331

The source of the experience


Concepts, symbols and science items



Science Items

Activities and commonsteps