# Dietary changes and cholesterol **URL:** \ **Category:** Factual Questions\ **Created:** [January 21, 2014, 12:00pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355 "2014-01-21T12:00:54Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![RitterSport](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rittersport/32/6326_2.png) [@RitterSport](https://boards.straightdope.com/u/RitterSport)\ **Post date:** [January 21, 2014, 12:00pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/1 "2014-01-21T12:00:54Z")
I guess this is a question for the doctors here, but I’m NOT asking for medical advice. Have there been any studies which measure how long it takes for dietary changes to affect cholesterol levels? I can’t seem to find the right search terms, or maybe there are no studies. The question really is, how long until you reach a new steady state, I guess. I imagine it doesn’t take too long to make some change. For example, let’s say my total cholesterol is 257 and I make some changes to my diet. Hypothetically, the changes to the diet should lower my cholesterol by, say, 10%, to around 230. When will the levels settle there? ---
**Author:** ![Antinor01](https://avatars.discourse-cdn.com/v4/letter/a/ecae2f/32.png) [@Antinor01](https://boards.straightdope.com/u/Antinor01)\ **Post date:** [January 21, 2014, 4:46pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/2 "2014-01-21T16:46:05Z")
Over 3 months I dropped mine over 30 points just by eating a bowl of oatmeal for breakfast every day. ---
**Author:** ![RitterSport](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rittersport/32/6326_2.png) [@RitterSport](https://boards.straightdope.com/u/RitterSport)\ **Post date:** [January 21, 2014, 6:30pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/3 "2014-01-21T18:30:13Z")
> [@Antinor01](#): > > Over 3 months I dropped mine over 30 points just by eating a bowl of oatmeal for breakfast every day. Congratulations! However, and I mean this without snark, I’m really looking for studies done that look at the time it takes for cholesterol levels to reach a new level, not for anecdotes. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [January 21, 2014, 6:34pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/4 "2014-01-21T18:34:27Z")
Note that for a solid minority, what you eat has little effect on your levels, your levels may be set more by your genes that your gut. In general, don’t expect big changes until you have been on the diet for six months. ---
**Author:** ![SpoilerVirgin](https://avatars.discourse-cdn.com/v4/letter/s/4491bb/32.png) [@SpoilerVirgin](https://boards.straightdope.com/u/SpoilerVirgin)\ **Post date:** [January 21, 2014, 6:36pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/5 "2014-01-21T18:36:59Z")
Here’s a [study](http://www.ncbi.nlm.nih.gov/pubmed/16522904?ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum) that seems to show some reduction after 3 months, and additional reduction after one year. ---
**Author:** ![Antinor01](https://avatars.discourse-cdn.com/v4/letter/a/ecae2f/32.png) [@Antinor01](https://boards.straightdope.com/u/Antinor01)\ **Post date:** [January 21, 2014, 6:42pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/6 "2014-01-21T18:42:53Z")
> [@RitterSport](#): > > Congratulations! However, and I mean this without snark, I’m really looking for studies done that look at the time it takes for cholesterol levels to reach a new level, not for anecdotes. I understand. 🙂 Was mostly replying to the 2nd part of the OP. ---
**Author:** ![RitterSport](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rittersport/32/6326_2.png) [@RitterSport](https://boards.straightdope.com/u/RitterSport)\ **Post date:** [January 21, 2014, 7:08pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/7 "2014-01-21T19:08:07Z")
> [@DrDeth](#): > > Note that for a solid minority, what you eat has little effect on your levels, your levels may be set more by your genes that your gut. > > In general, don’t expect big changes until you have been on the diet for six months. Understood. > [@SpoilerVirgin](#): > > Here’s a [study](http://www.ncbi.nlm.nih.gov/pubmed/16522904?ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum) that seems to show some reduction after 3 months, and additional reduction after one year. Perfect, thanks. So, if the non-doctor is right that it may be controlled by genes, a test at three months could indicate whether dietary changes will do any good. If those changes are helping, the full effect may not be known for six months or a year. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [January 21, 2014, 8:08pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/8 "2014-01-21T20:08:47Z")
Decent summation. ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [January 21, 2014, 9:06pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/9 "2014-01-21T21:06:19Z")
In the late 1990s, I worked for Quaker Oats; in 1997, the FDA approved a cholesterol-reduction claim for oatmeal. As part of that claim, we were allowed to point to clinical research which showed that eating oatmeal\* every day for 30 days led to an average reduction in overall cholesterol levels of about 15 points. We did a series of ads (and PR outings) called “The Smart Heart Challenge”, where we’d go to various towns, and get the local residents to sign up for a 30-day program, and get their cholesterol levels checked before and after. Generally speaking, people who stuck with it for 30 days did usually see results along those lines. But, there was certainly variation in this. The average was 15 points or so, but some people (as **DrDeth** suggests above) didn’t see a drop at all, while others had a bigger drop. \*- This was a good-sized bowl of oatmeal, about 1 1/2 times the “serving size” on a box of regular oats, or about 3 packets of instant oatmeal. ---
**Author:** ![UncleFred](https://avatars.discourse-cdn.com/v4/letter/u/f0a364/32.png) [@UncleFred](https://boards.straightdope.com/u/UncleFred)\ **Post date:** [January 21, 2014, 9:32pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/10 "2014-01-21T21:32:16Z")
> [@DrDeth](#): > > Note that for a solid minority, what you eat has little effect on your levels, your levels may be set more by your genes that your gut. Minority reporting in here - I’m slim and somewhat athletic, but I have _always_ had a relatively high count, going back to when I was first tested in my early 20’s. It’s completely independent of diet - I can eat ‘well’ and watch the count go up, or eat poorly and watch it go down. The other way around happens also. I do have a moderately high ‘good’ cholesterol, so my family doctor has never been worried about my total count. ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [January 21, 2014, 10:00pm UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/11 "2014-01-21T22:00:12Z")
> [@UncleFred](#): > > Minority reporting in here - I’m slim and somewhat athletic, but I have _always_ had a relatively high count, going back to when I was first tested in my early 20’s. It’s completely independent of diet - I can eat ‘well’ and watch the count go up, or eat poorly and watch it go down. The other way around happens also. > > I do have a moderately high ‘good’ cholesterol, so my family doctor has never been worried about my total count. That’s important. I hear so much about high cholesterol, but not the different factions of cholesterol. If you have high HDL naturally your total cholesterol will be higher. The ratio is what’s important. Borderline is 4:1’ i.e. total cholesterol 200, HDL 50. Better is 3:1 (total cholesterol 200, HDL 67. Best is 2:1 or greater (total cholesterol 200, HDL 100). Your liver synthesizes cholesterol because cholesterol is needed for various reasons. Note that ingestion of cholesterol is a minor player in total cholesterol. Eating meat and fats is the important factor. For example, trans fats increases LDL and decreases HDL, just the opposite of what you want. Saturated fats increase LDL, and unsaturated fats have various other effects, whether they are polyunsaturated or monounsaturated. Niacin (over the counter), which is a B vitamin, is good for lowering LDL cholesterol. LDL cholesterol also has various factions, and it very low-density cholesterol which is the worst because that tends to adhere to blood vessel walls. The HDL helps clean the wall. ---
**Author:** ![Matt1075](https://avatars.discourse-cdn.com/v4/letter/m/94ad74/32.png) [@Matt1075](https://boards.straightdope.com/u/Matt1075)\ **Post date:** [January 22, 2014, 9:38am UTC](https://boards.straightdope.com/t/dietary-changes-and-cholesterol/679355/12 "2014-01-22T09:38:31Z")
@Rittersport- if you are concerned about cholesterol levels, you may want to take a look at coconut oil. Here’s a good link to get you started: [http://coconutoil.co/coconut\_oil\_heart\_disease/](http://coconutoil.co/coconut_oil_heart_disease/)