Pooch & Mutt always look for protein sources most relevant to the condition that the food is created for, as the protein source makes up 45% of the food. For Calm & Relaxed the protein source is turkey, as turkey is a protein source rich in L-tryptophan (which some state as the reason for increased lethargy after Christmas lunch.)
As well as being a great source of fibre and b-vitamins (see above), on a macronutrient level sweet potato is a source of carbohydrate. Carbohydrates stimulate the production of insulin, which induces the uptake of branched chain amino acids (BCAAs), excluding tryptophan, into the muscles (source www.vetsci.co.uk). The BCAA uptake by the muscles reduces the competition for tryptophan at the blood-brain barrier therefore making it easier for tryptophan to cross the blood-brain barrier and be more effective.
L-tryptophan is a precursor of serotonin, i.e. it is used by the body to make serotonin. Serotonin is a neurotransmitter that plays a large role in controlling mood, behaviour and cognition. It can create feelings of well-being and relaxation. (Most prescription antidepressants are in the class SSRI – Selective Serotonin Re-uptake Inhibitors – which counteract depression by increasing the amount of serotonin in the brain). “When levels of serotonin are high you are in a better mood, sleep better and have a higher pain tolerance” says Elizabeth Somer MA RD, author of ‘Eat your way to happiness’ (source www.webmd.com).
Serotonin is, in turn, used by the body to create melatonin, a hormone that helps to regulate sleep patterns. L-tryptophan has been shown to decrease agression in dogs (De Napoli et al, 2000) and decrease stress responses (Pereeira et al, 2010).
B-vitamins in ‘Calm & Relaxed’ come from sweet potato and brewers yeast. B-vitamins are known as the ‘anti-stress vitamins’. It has been proven that vitamins B1, B3, B6, B8 and B12 support the availability and production of key neurotransmitters such as serotonin, noradrenaline, GABA and dopamine (Combs GF, 2008).
Participants in a 90 double-blind, randomised, placebo-controlled trial reported significantly lower personal strain and a reduction in confusion and depressed/dejected mood after 12 weeks. (Centre for Human Psychopharmacology, 2011) Vitamin B-6 in particular plays an important role in the synthesis of serotonin and the metabolism of tryptophan to serotonin (see L-tryptophan above) (source www.vetsci.co.uk)
Chamomile has a long history as a relaxation aid, with use dating back to ancient Egypt. Chamomile is thought to help regulate levels of cortisol. Cortisol is the hormone released in the body in times of stress and is the main signifier of stress. Helping to regulate cotisol means returning from a stressed state to a relaxed state in as short a time as possible.
Chamomile contains the flavnoid apigenin which acts as a natural sedative, relieving anxiety and stress (Viola H, Wasowski C et al, 1995). Chamomile serves as a general purpose calming ‘calming herb’ that can be fed to animals as a ‘first try’ remedy for any variety of spasmodic or anxiety related problems (G Tilford, The Animal Herbalist, 2010).
PROBIOTICS & PREBIOTICS
There is a cyclical relationship between stress and digestion. Stress both causes and is caused by digestive issues. Stress produces cortisol, which in turn compromises digestion and absorption, indigestion follows and he mucosal lining becomes irritated and inflamed… The resulting mucosal inflammation leads to the increased prodction of cortisol, and the cycle continues (Diana Aronson, Today’s Dietician).
Probiotics and prebiotics help to break this cycle by promoting the optimal functioning of the digestive system. Using probiotics proactively can reduce the risk of situations that tend to spur gastrointestinal upset in certain situations, like boarding or post antibiotic use. Animal shelters are using probiotics more and more because of the stress that dogs feel. Traveling with a pet and diet changes can create an intestinal microflora upset, which probiotics can help minimise (Dr Grace Long DVM MS MBA, 2012). Parallel studies at McMaster University, Ontario and The Alimentary Pharmabiotic Centre, Cork showed that probiotics could lead to fewer visible signs of anxiety, lower levels of stress hormones and chemical changes in the brain (J Cryan, 2011).
Further studies have confirmed the links between probiotics and brain activity, such as Dr E Mayer from The University of California, Los Angeles who, using MRI images found connections between different regions of the brain depending on which type of bacteria was most abundant in the gut. A summary of probiotic research was compiled by the Daily Mail in January 2014.