Should Your New Year Include a Detox Diet? What the Science Says

With the start of the new year, companies are capitalizing on your New Year Resolutions by advertising popular detox diets and cleanses. This is one of the reasons that I started the HealthySelf Reset with my friends and functional medicine doctors, Julie Foucher, MD, MS and Dani Urcuyo, MD—to provide a fresh reset in the new year for free. In doing this we aim to help give you a boost for the new year and start it out as your healthiest self—no quick fixes, extreme dieting, or juice cleanses are included in our program. But what about detox programs as a whole—do they actually help?

Controversy with Detox

The topic of detoxification can be polarizing—while you will hear a lot of bloggers talk about the importance of detoxing, you will not commonly hear this anyone in the healthcare profession or academia. And that’s because most healthcare practitioners—or people that have actually studied biochemistry, anatomy, nutrition, etc. will tell you that the liver is able to detox on its own. In fact, one of the main roles of the liver is to process and excrete chemicals, toxins and other substances that you are exposed to through urine, sweat and stool. So, if you drink water and have a bowel movement then many healthcare practitioners will tell you that you are detoxing perfectly fine.

Environmental Pollutants

While research and principles of biochemistry support the idea that the liver is always detoxing, there are two main reasons for why a person may need additional detox support. The first is that within recent years, exposure to chemicals, environmental pollutants, and toxins in the environment have significantly increased. And it is unclear of whether the liver is able to take care of this additional toxic burden. A 2018 paper from the American Academy of Pediatrics identified that there are more than 10,000 chemicals that are allowed to be added to food and food contact materials (aka all of the plastic packing that your food is wrapped in at the grocery store) in the United States. That’s just in our food! When accounting for environmental chemicals, it’s estimated to be over 30,000.

This is in part due to the 1958 Food Additives Amendment to the 1938 Federal Food, Drug, and Cosmetic Act (FFDCA) which allows a number of food additives to be added to the food supply if they are on the Generally Recognized as Safe List (GRAS). This act states that any substance that is intentionally added to food is a food additive that is subject for pre-market approval by the FDA unless it is on the GRAS list. Some foods however did not require a pre-market approval if they had been used for long enough or based on the nature of the substance. This allows for additives in our food to be included either directly or indirectly into the product without fully understanding their safety. Indirect food additives include bisphenols, phthalates, and perfluoroalkyl chemicals (PFCs), while direct food additives include nitrates/nitrites that are found in food packaging.

While there is clearly a large number of chemicals in the food supply, what’s just as and if not more concerning is the number in our environment. A 2011 research review reported that 4.9 million deaths (8.3% of total deaths) were attributable to environmental exposure such as indoor smoke from sold fuel, outdoor air pollution, and second hand smoke. Additional exposures that they found attributable to environmental factors included occupational particles, chemicals involved in acute poisonings and pesticides involved in self-poisonings. The current research has established a correlation between your environmental exposure to chemicals and an increased risk of respiratory infections and chronic respiratory diseases; perinatal conditions; congenital abnormalities; cancer of the lung, skin, liver, brain, kidney, prostate, bone marrow and bladder; cognitive dysfunction; Parkinson’s disease; Attention-deficit disorder; and hearing loss.

Examples of Human Exposure to Toxins

-Outdoor Air

Example: the environmental pollutants that you inhale daily such as vehicle exhaust, tobacco smoke, particles from industrial emissions, etc. 

-Indoor Air

Example: the pollutants that you inhale indoors daily such as tobacco smoke, furniture, carpet, construction materials, etc.

-Drinking Water

Example: tap water contaminated with pesticides, herbicides, heavy metals (lead, mercury, arsenic), and industrial solvents due to agricultural runoff, human dwellings, etc.


Example: Chemicals such as pesticides, methylmercury, lead, etc. consumed through food due to agricultural practices and environmental contamination.

-Non-food Consumer Products

Example: Food containers, chemical products, cleaning products, skincare products, etc.


Example: Ingestion of soil contaminated with pesticides or other chemicals from agricultural processes.

Occupational Exposure

Example: ingestion of chemicals or by-products of industrial processes such as agricultural mining. 

-Human to Human

Example: fetal exposure to toxic chemicals such as mercury during pregnancy.

The Role of Genetics

The second reason involves genetics. Many people have various SNPs or genetic variants that impair their ability to detox appropriately. This may be why two different people can live in the same mold-ridden basement but yet only one person gets sick and the other person is unaffected. Specific genes that impact a person’s ability to detox include CYP1A1, GSTM1, GSTP1, GSTT1. If you have a high sensitivity to a lot of chemicals, smells, etc. then you may want to take a closer look at your genetic profile. While you cannot change your genes, you can change the expression of them through targeted nutrition and lifestyle interventions.

Due to the concern of the increased toxic burden and the risk of having various genetic mutations, it doesn’t hurt to add additional detoxification to assist the liver in doing its job. But it’s important to note that you should not trust all ‘detoxes’ and ‘cleanses’ out there that over-promise results and tend to lack scientific evidence.

The recommendations for decreasing your toxic load are two pronged but they include 1) minimizing unnecessary toxic exposure and 2) enhancing your body’s ability to detox.

How to Minimize Toxic Exposure in your Diet

1. Buy a Water Filter

Water is one of the number one sources of chemicals and heavy metals such as lead. There are health guidelines in place that deem the safest level of each of these contaminants but most city water detects levels that are above those guidelines. You should know what the state records say about your water, based on your zip code. Go to the Environmental Working Group’s (EWG) Tap Water Database to enter your zip code to find out how polluted your drinking water is and which contaminants your water is highest in. Then you can search on their website for a water filter that filters out whose specific contaminants.

2. Avoid Drinking Out of Plastic Bottles

That goes for adults and babies! It’s best to avoid reusable plastic water bottles and baby bottles that are lined with Bisphenol-A (BPA) and phthalates. BPA is a commercial plasticizer that is found in the lining of canned foods & drinks, water bottles, plastic baby bottles, and cash register receipts–there are over 8 billion pounds produced every year. Research shows that it is associated with adverse perinatal, childhood and adult health effects such as asthma. Phthalates are esters of diphthalic acid which are commonly used during the manufacturing process of lubricants and plasticizers. Studies show that BPA is able to leach from the storage container into the water. In one study, there were detectable levels of BPA in all room temperature water samples that had been stored in a polycarbonate water bottle.

3. Replace Storage Containers with Glass

This is worth the investment to have glass storage containers in the kitchen. Especially given that many people clean their Tupperware in the dishwasher which exposes the plastic to high temperatures. If you do end up having some plastic storage containers, you should absolutely avoid washing them under high heat.

4. Avoid Eating Fish that is Higher in Heavy Metals

It’s important to be smart when purchasing your seafood. Some fish is higher in mercury, Polychorinated Biphenyls (PCBs), and Polybrominated diphenyl ethers (PBDEs). One of the biggest concerns is high levels of mercury which is a neurotoxin that can impair cognitive function. The best fish to purchase tend to be those that are smaller such as scallops, sardines, anchovies, etc. The fish that are highest in mercury that are best to limit or avoid include tuna (albacore, yellowfin, bigeye, ahi); orange roughy; swordfish; grouper; king mackerel; halibut; and sea bass. For more information on purchasing safe seafood, use this NRDC guide.

5. Purchase Organic When it Comes to Meat, Dairy and Certain Fruits & Veggies

The produce that are most important to purchase organic include strawberries, apples, spinach and other fruits and vegetables that are included on the EWG Dirty Dozen list. This list includes those that are highest in pesticides that are more important to buy organic, compared to their Clean 15 list which is lower in pesticides.  

Simple Tips to Enhance Your Body’s Ability to Detox

1. Stay Adequately Hydrated

Hydration is a basic but powerful way to ensure that your liver is detoxing appropriately. Think of water as having the ability to flush harmful environmental pollutants from your system.  

2. Add Detox-Promoting Vegetables into your Diet

Vegetables are critical for detoxing because it is a very nutrient-dependent process to go through phase 1 and 2 of detox through the liver. Eating a variety of colors is also a great way to decrease the cell’s exposure to free radicals during this process.

Specific detox-promoting vegetables are those than contain sulfur and have the ability to bind to various contaminants and help remove them from your system. This includes the cruciferous vegetable family such as broccoli, cauliflower, bok choy, mustard greens, kale, cabbage, brussels sprouts, arugula, watercress, daikon radishes, and other allium vegetables such as garlic and onion. Aim for two cups of cruciferous vegetables daily! Also broccoli sprouts will give you the most detox-bank because a little goes a long way!

3. Aim for 30-40 Grams of Fiber Daily

Fiber is found in vegetables, fruits, nuts, seeds and beans/lentils. It not only binds to cholesterol and removes it from your body, it can do a similar thing with contaminants that would otherwise be stored in your fat cells. Eating adequate fiber is key for proper elimination. This also helps with promoting bowels which is an important part of detoxing.

4. Eat More Omega 3s and Fewer Omega 6s

When it comes to protecting the body from harmful environmental pollutants, omega 3s are one of the most important anti-inflammatory nutrients. This is why it’s important to eat at least 2-3 servings of low mercury, omega 3 rich fish per week such as wild salmon, sardines, anchovies, herring, cod, and scallops. In my experience of interpretting thousands of omega 3 blood tests, omega 3 deficiencies are very common so you may also need a high quality omega 3 supplement. Research suggests that eating more omega 3s and fewer omega 6s (which can be found in canola oil, sunflower oil, safflower oil, cottonseed oil, soybean oil, corn oil, peanut oil, etc.) can decrease the inflammatory response that happens from exposure to PCBs.

5. Prioritize Detoxing from Toxic Emotions, Relationships and Environments

Toxicity can also heighten when you keep toxic people in your life, ignore your emotions, and resent other people for their wrong doings. Part of enhancing your body’s ability to detox involves emotional releases, forgiveness, and surrendering your control. While there is not as much research on this particular topic, it is an important part of your emotional and spiritual health.

These are just a few ways that you can start to decrease your toxic exposure through your food and water intake. Stay tuned for more on how to decrease your overall toxic burden and specific nutrients that aid in this process. In the meantime, please submit any questions or comments that you have on this topic.

For additional information on liver health, specifically for those with fatty liver disease, I would recommend Skinny Liver by Kristin Kirkpatrick, MS, RDN, LD.