Low blood sugar appears to cause aggression and relationship disharmony

Back in 2011 I wrote a blog post that focused on a case of alleged domestic violence. In short, a judge had come home after work, but his wife was busy giving support to a visitor. The judge took himself off upstairs as dinner was clearly going to be delayed. Later that evening, it was alleged the judge repeatedly punched his wife in the face. The judge was subsequently found guilty. In my blog post, I put forward the idea that perhaps the delayed dinner was a factor in the alleged violence. I suggested that hunger and low blood sugar can trigger mood changes and increased aggression and excitability that could contribute to violence and anti-social behaviour.

I was therefore very interested to read a new study in which researchers attempted to assess the relationship between blood sugar levels and aggression in married couples [1].

Aggressive impulses were assessed by asking individuals to stick pins in a voodoo doll representing their partner (I know, not necessarily a nice thought). Aggressive behaviour was assessed by allowing individuals to play sounds into headphones worn by their partner. Individuals were free to choose the loudness and level of the sound. Louder and more sustained sounds were taken as a sign of higher aggression.

The researchers found that lower blood sugar levels were associated with an increase in both aggressive impulses andaggressive behaviour.

Of course, undue hunger and low blood sugar may have some other adverse effects too, such as driving individuals to overeat (often none-too-healthy foods, too) and drink more alcohol than they otherwise would.

In short, those seeking to make healthy eating and harmonious relationships as easy as possible should avoid getting too hungry. A snack of something sustaining (e.g. nuts, biltong, cold meat, a hard-boiled egg) in the late afternoon or early evening will usually do the trick.


1. Bushman BJ, et al. Low glucose relates to greater aggression in married couples. PNAS USA 2014 Apr 14. [Epub ahead of print]


12 Responses to Low blood sugar appears to cause aggression and relationship disharmony

  1. Soul 18 April 2014 at 5:08 pm #

    I looked at this more from a comical stand point. It’s not all comical though of course. A few weeks ago there was an incident regarding a Hollywood star, her investment into a soda pop company, which then led me to remembering your original post mentioned in this writing, along with how eating lower carb/sugar meals tends to result in fewer hunger pains.

    What happened is actress Scarlet Johansson invested into an Israeli owned soda pop company. The firm runs its canning operations in a Palestinian area and employees many Palestinians. Some felt this to be a positive company. It was trying to build bridges between the two warring groups. Many feel that more trade between Palestinians and Israelis could lead to a more peaceful existence in that troubled part of the world. Sadly some disagreed with Johansson’s investment though, and let her know about it. She was forced out of Oxfam.

    When I saw the news, and the controversy it had me thinking, nice idea, in part. More trade and more jobs generated between the two embittered groups would be a plus it seems to me. Couldn’t there be better ideas though on cross trade? I had a hard time wrapping my mind on the idea that Palestinians and Israelis could drink more caffeinated, sugary drinks and as a result of this be more friendly. Maybe the old 1970s Coke commercial of perfect harmony is true?

  2. Robert Park 18 April 2014 at 7:30 pm #

    Allergies, and their effect on behaviour, caused by food or its lack, is not new. There has been studies done on prisoners which showed an improvement in behaviour but those studies are questionable as whenever the focus of attention is on individuals or groups, behaviour always changes and apparently in the direction of the observer’s expectations (C.Jung & W Brown). This is similar to what Dr Bruce Lipton refers to as ‘the honeymoon effect’ or one’s belief affecting both behaviour and health. I would suggest that it may not be the food (or its lack) that affected the Judge but another problem that was either not discovered or revealed. What probably can be deduced from the Judge’s behaviour is that he lost control or reacted in a child-like manner. Once more, this returns to the perpetual battle between nature and nurture. People who are egocentric have difficulty at viewing circumstance objectively although the Judge’s legal training should have developed this trait but may have failed to do so. The inability to be objective, as far as this is possible, is liable to cause irrational or reactionary behaviour but, having said this, it does appear that the allergic effect of foods or drugs can be a contributory feature.

  3. Mark. 19 April 2014 at 2:00 am #

    As an insulin-dependent diabetic (type 1 for over 40 years), I can vouch for my own aggressive behavior when I’m having an insulin reaction. I’m sure my family can as well. When blood glucose is really low it’s more cold sweats and weakness, but when it’s a bit higher I’m very short-tempered. Generally I know to start eating the 4-gram glucose tablets I normally carry, vile as they are.

  4. kem 19 April 2014 at 5:11 am #

    Tell me about it. My beautiful wife always made sure I had come carborific snack at hand before I learned to run on fat.

  5. Marie 19 April 2014 at 7:10 am #

    Certain medications can also cause irritation, aggression etc. as side effects.
    Please read Peter R. Breggin`s book – Medication madness.

  6. jili 19 April 2014 at 8:58 am #

    This rings a loud bell with me because when I’m hungry I always seem to get bad tempered, and, yes, aggressive, although certainly not to the point of physical violence.

    A partner many years ago used to refer to it as ‘tantrum time’ and I have often felt ashamed about showing off just because I’m hungry! Rather like a spoilt child. However now I know that if this happens I should just eat something, however small, at once.

  7. Aurelie 19 April 2014 at 11:38 pm #

    Yes I have read many studies linking nutritional deficiencies with aggressively. One famous example in pellagra…. but also sturdies made in the Netherlands in prisons where after nutritional deficiencies where addressed acts of violence were drastically reduced within the prison…..

  8. Jennie 20 April 2014 at 6:11 pm #

    Yes this rings bells with me too! There can definitely be a change of mood if your blood sugar drops and you are hungry! I was always ‘peckish’ at the wrong time until I changed my diet very dramatically, thanks to Dr Briffa, Malcolm Kendrick and the likes. I’m sure it runs in the family too as I remember quite clearly now , my Father coming home from work in the evenings, and if he had to wait a while for his evening meal then it was best to keep out of his way! My poor Mother used to get the table set and have pans of water bubbling on the cooker to make him think dinner was almost ready! The old sugar/carb rush followed by a crash a short time after was I’m sure what the problem was with him. Sandwiches and cake for lunch, chocolate biscuits in the afternoon………..

    Thanks Dr B for all your wisdom

  9. Liz 20 April 2014 at 6:52 pm #

    My Mum taught me this 50 years ago (and knew herslf some 30 years before that) – that not having eaten (especially pre-menstrually) could lead to being grumpy and irritable – and even to being uncharacteristically violent – she once threw a saucepan at my dad at such a time! I tied it to low blood sugar when training as a nurse in the early 70s, and seeing an insulin-dependent diabetic on the ward become irritable and irrational when she had a hypo, in a manner very similar to what we experienced as non-diabetics.
    Since then, I’ve always referred to myself at such times as going “hypo”, and would also get dizzy and sweaty. First, in the 80s I learned from Dr Katherina Dalton to eat something starchy 3 hourly, premenstrually to avoid the hypos, and later learned that avoiding sugar completely helped, then that avoiding any refined carbs and eating protein with carbs helped, finally coming to limit my carb intake.
    A couple of years ago, when foolishly I ate quite a bit of refined carb food with very little protein, to be polite because someone had prepared it specially for me, I experienced a sweaty dizzy irritable hypo some hours later – the first for a long time. I had access to a blood sugar meter, and my bs was 2.5


  1. <b>Low blood sugar</b> appears to cause aggression and relationship <b>…</b> | Gluco-Solve - 18 April 2014

    […] <b>Low blood sugar</b> appears to cause aggression and relationship <b>…<… […]

  2. [Fan Club] LCHF Lifestyle - Part 3 - Page 254 - www.hardwarezone.com.sg - 22 April 2014

    […] Low blood sugar appears to cause aggression and relationship disharmony | Dr Briffa's Blog – A Good … __________________ 1st time iHerb users – get 10% off using my code – YAQ580 […]

  3. Low blood sugar and aggression – and ‘dirty’ fruit and veg - 10 May 2014

    […] read this post on low blood sugar and aggression on Dr John Briffa’s blog a couple of weeks ago – and […]

Leave a Reply