Blood sugar

What raises blood sugar?

Insulin helps cells absorb glucose. In type 2 diabetes its action is impaired. 1

How is it assessed?

Blood tests measure glucose; HbA1c reflects the preceding 2 to 3 months. Thirst and frequent urination can occur, but diabetes may remain symptomless for years. 1

When does it need medical attention?

Very high glucose can cause impaired consciousness. Diagnosis requires clinical assessment and blood testing. 1

Why can readings change?

In people with diabetes, illness, stress, reduced activity and missed medication can raise glucose. Steroid medicines are another possible trigger. Persistent high readings or symptoms in someone without a diabetes diagnosis warrant medical assessment. 2

Which symptoms are urgent?

Suspected high glucose together with vomiting, abdominal pain, rapid breathing, confusion or marked drowsiness requires urgent medical help. These can signal a serious metabolic emergency. Diabetes medication should not be stopped or adjusted without the care team’s advice. 2

Do supplements help?

Evidence is limited by small studies and variable preparations. Supplements cannot replace effective treatment. 3

berberineToo little evidence

Reviews suggest benefit, but study quality and generalizability are limited. 3

chromiumToo little evidence

Some trials suggest improved glucose markers; long-term safety is poorly studied. 3

cinnamonToo little evidence

Possible improvements require confirmation with standardized preparations. 3

What did randomized trials find?

Guo and colleagues pooled 46 trials with 4,158 participants, lasting 4 weeks to 6 months. Participants had type 2 diabetes or prediabetes; interventions included berberine and some plant preparations. The pooled HbA1c difference was -0.73 percentage points. This heterogeneous analysis combines different comparators and treatment combinations, so it is not a direct estimate of replacing medication with berberine. 4

What matters beyond supplements?

Movement, dietary changes and, when necessary, medication are established components of diabetes care. 1

What this review covers

This page reviews selected nutrients; it does not assess every imported nutrient rating.

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