Because everyone's body is different, we'll each have different reactions to sugar intake - and each of us has a different personal symptoms towards increased intake of sugar...
Mood Swings
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If you haven't been feeling like the best or happiest verse of yourself, your diet could be blamed. An increased sugar diet can cause severe mood swings. This is due to the rise and fall in blood glucose levels. Reducing your intake of sugary foods would potentially balance out your mood and lead to more positive feelings overall.
Acne
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You thought you outgrow acne as a grown up ? Or you thinking it is but your diet had other plans for your skin.... Ingesting high levels of sugar has been linked to hormone imbalances.
Plan of action: keep your skin routine the same, but just start reducing your sugar intake.
Headaches
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Common symptoms of hypoglycemia can include headaches or migraines. If you experience headaches often, you may be eating excessive amounts of sugar.
Weight Loss
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If you're constantly and eating pretty healthy but still not losing weight, it's time to reassess your diet's sugar levels.
Hormonal Imbalances
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In women esp., a sugary diet could be linked to different hormonal issues, this is specifically true for women with polycysitc ovarian syndrome, caused by stress and excessive sugar intake.
Summary fact: stress can also cause all of the aforementioned symptoms that sugar can . . . so eating sugar is almost like eating stress.
Hyperglycemia
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Increased intake of sugar will increase storage of sugar by the liver... The liver stores excess sugar to be converted to glucagon in the liver, and when needed it is converted to glycogen then to glucose for easy usage... But when there is excess in the body, the body will make use of the one needed, even the ones to be stored is also stored and there is still excess, therefore there is hyperglycemia shock or Diabetes Mellitus as prognosis..