There's no evidence that drinking a series of juices, teas, or any of other so-called 'detox' products does anything besides profit the people selling them.
There are no shortcuts to health.
A toxin is something that can be harmful to you, but this is about as broad a term as it gets. There's a spectrum; toxicity depends on what it is and how much you take in.
The urge to detoxify your body when a new year starts has nothing to do with a buildup of toxins. Feeling bloated and fatigued is the result of the all the holiday eating.
Everything you eat goes to your liver and it determines what to do with the components of what you've ingested:
If it's something useful the liver sends it out into circulation, but if it's not immediately usable or could be harmful, your liver has enzymes to neutralize it and send it off as waste to be removed from the body through urine, mostly. The best you can do to help your liver out is to hydrate and exercise.
The enzymes your liver is using to break down unwanted compounds are made from substances in certain foods you eat—specifically whole fruits, vegetables, and protein.
You should be having whole fruits and vegetables, five to nine servings a day. The juice is not a substitute, as it lacks the fiber your body needs to support waste removal in the liver and in your intestines.
Carbs, protein, and fat are the trifecta of perfection for keeping your body healthy.
When you eliminate these important nutrients, you may see slowed metabolism from drastically decreasing calories, dry skin, decreased energy, and crankiness.
Detox diets are generally short-term dietary interventions designed to eliminate toxins from your body.
A typical detox diet involves a period of fasting, followed by a strict diet of fruit, vegetables, fruit juices, and water. Sometimes a detox also includes herbs, teas, supplements, and colon cleanse or enemas.
Human research on detox diets is lacking, and the handful of studies that exist are significantly flawed