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Could “Relative” Hypoglycemia Be Causing Your Anxiety?

Food-triggered shifts in blood sugar can worsen anxiety and wreck your mood.

ZeeNBee / PIxabay
Source: ZeeNBee / PIxabay

Are you an anxious person? Do you also frequently experience symptoms of hypoglycemia? The two may be closely related.

My first memory of “hypoglycemia” happened when I was in my early thirties, while shopping for groceries. One minute I was fine, and then the next I felt lightheaded, weak, anxious, irritable and tearful. At first, I didn’t know what was wrong. When it dawned on me that I might have low blood sugar, I quickly ate something and felt better. And felt embarrassed about how I had acted! Crying in a grocery store, for no reason at all, isn’t pretty.

After that episode, it happened enough times that I started carrying candies or meal bars in my purse. I couldn’t go for more than a couple of hours without eating, during the day. During times that I felt inexplicably anxious or irritable, a solid healthy meal would typically turn my mood around. Completely. I’d feel calm and normal after, other than feeling embarrassed (yet again!) if I’d been tearful, weirdly anxious or touchy prior to eating.

Over the years, I’ve frequently counseled patients with anxiety to eat regularly and avoid high sugar foods. Best not to let blood sugar get too low, and avoid the dramatic swings in blood sugar that refined carbohydrates trigger, as this would exacerbate (or mimic) their symptoms.

Recently, I came across an explanation of how important it is for people with anxiety or depression to eat a solid meal first thing in the morning. The directive was to eat a breakfast high in fat and protein, as soon as possible after getting up. If an anxious or depressed person were to attempt a demanding task without having a decent breakfast first, they could end up “psychophysiologically unstable” for the rest of the day.

The physiology behind this is that the stress of the complex task (on a fasted body that hasn’t eaten anything yet) causes insulin hypersecretion, which further lowers blood sugar, throwing the body and brain off-kilter and making the person feel physically and emotionally unstable. In a way that’s hard to recover from.

Reading this, I realized that that person was me! I’ve noticed that on Sunday mornings I often feel weirdly irritable or stressed. It’s strange because I’ve normally slept very well and have no reason to be irritable or stressed. Now that I think about it, though, we sleep in on Sunday mornings before heading to church. My breakfast tends to be much later than usual.

There are some fascinating studies in this area. A classic one was published in 1966 by Harry Salzer: Reactive Hypoglycemia and Neuropsychiatric Illness. He described reactive (or “functional”) hypoglycemia as a relative drop in blood sugar that profoundly affected vulnerable individuals, even though their blood sugar never dropped into an officially hypoglycemic range. They would have symptoms of hypoglycemia, without low blood sugar. A relative drop in blood sugar, however, could be observed via a six-hour glucose tolerance test (rather than using the gold standard fasting blood glucose test to test for classic hypoglycemia).

The symptoms of hypoglycemia included depression, anxiety, insomnia, irritability, crying spells, forgetfulness, trembling, racing heart and dizziness (I know these well!). He also observed that the patients suffering from these symptoms were typically eating a diet high in refined carbohydrates and caffeinated drinks.

When he treated them with a high protein, low sugar, caffeine free diet, the “anxiety” symptoms completely resolved in many patients. This was attributed to a smoothing out of blood sugar and insulin levels (both sugars and caffeine can trigger wild swings in blood sugar and insulin secretion).

Another interesting paper was published in the 2016 Case Reports in Psychiatry. A 15-year-old teenager with generalized anxiety disorder and symptoms of hypoglycemia had been eating a diet primarily made up of refined carbohydrates.

They added more protein, fat, and fiber to her diet over a four week period. For example, they traded out her usual breakfast fruit/fruit juice smoothie for one with whole fruit, protein powder, and flax seeds. Her anxiety symptoms decreased dramatically. She also experienced improved energy, less frequent hypoglycemic episodes, and improved concentration and mood.

A few weeks later, she briefly returned to her old way of eating. Her anxiety symptoms returned immediately.

There’s lots of other data out there — for example, a cohort study that showed an association between an increased risk of depression and anxiety and consumption of foods with a high glycemic index.

I worry that today’s near-obsessive emphasis on “time-restricted eating” and fasting (which can have profound benefits in some, to be sure), may cause significant neuropsychiatric mood problems in people vulnerable to anxiety and depression. I’m certainly one of those, which is why I can’t do intermittent fasting on a daily basis. I learned that very quickly, after trying it! I need to eat to stay sane, literally.

In fact, I’m going to start eating breakfast even earlier than I already do. I'll also make it much more hearty.

Copyright 2018 Dr. Susan Biali Haas

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