Taking time for kind thoughts about yourself and loved ones has psychological and physical benefits, a study has found.

Researchers from University of Exeter and University of Oxford in the UK found that taking part in self-compassion exercises calms the heart rate, switching off the body's threat response.

Previous studies have shown that this threat response damages the immune system.

Researchers believe the ability to switch off this response may lower the risk of disease.

Questions included how safe they felt, how likely they were to be kind to themselves and how connected they felt to others.

The two groups whose instructions encouraged them to be kind to themselves not only reported feeling more self-compassion and connection with others, but also showed a bodily response consistent with feelings of relaxation and safety.

Their heart rates dropped and the variation in length of time between heartbeats - a healthy sign of a heart that can respond flexibly to situations. They also showed lower sweat response.

Meanwhile, instructions that induced a critical inner voice led to an increased heart rate and a higher sweat response - consistent with feelings of threat and distress.

"By switching off our threat response, we boost our immune systems and give ourselves the best chance of healing. We hope future research can use our method to investigate this in people with mental health problems such as recurrent depression," Anke Karl, of the University of Exeter.

The recordings that encouraged self-compassion were a "compassionate body scan" in which people were guided to attend to bodily sensations with an attitude of interest and calmness; and a "self-focused loving kindness exercise" in which they directed kindness and soothing thoughts to a loved one and themselves.

The three other groups listened to recordings designed to induce a critical inner voice, put them into a "positive but competitive and self-enhancing mode", or an emotionally neutral shopping scenario. All the audio recordings were 11 minutes long.

The signs of this were reduced sweat response and heart rate slowed by two to three beats per minute on average, compared to the groups listening to critical voice recordings.

The self-kindness groups also showed increased hear rate variability -- a sign of a healthy heart that is able to adapt to a range of situations.